sf
objectaggregate an sf
object, possibly unioning geometries
## S3 method for class 'sf'
aggregate(
x,
by,
FUN,
...,
do_union = TRUE,
simplify = TRUE,
join = st_intersects
)
x 
object of class sf 
by 
either a list of grouping vectors with length equal to 
FUN 
function passed on to aggregate, in case 
... 
arguments passed on to 
do_union 
logical; should grouped geometries be unioned using st_union? See details. 
simplify 
logical; see aggregate 
join 
logical spatial predicate function to use if 
In case do_union
is FALSE
, aggregate
will simply combine geometries using c.sfg. When polygons sharing a boundary are combined, this leads to geometries that are invalid; see https://github.com/rspatial/sf/issues/681.
an sf
object with aggregated attributes and geometries; additional grouping variables having the names of names(ids)
or are named Group.i
for ids[[i]]
; see aggregate.
Does not work using the formula notation involving ~
defined in aggregate.
m1 = cbind(c(0, 0, 1, 0), c(0, 1, 1, 0))
m2 = cbind(c(0, 1, 1, 0), c(0, 0, 1, 0))
pol = st_sfc(st_polygon(list(m1)), st_polygon(list(m2)))
set.seed(1985)
d = data.frame(matrix(runif(15), ncol = 3))
p = st_as_sf(x = d, coords = 1:2)
plot(pol)
plot(p, add = TRUE)
(p_ag1 = aggregate(p, pol, mean))
plot(p_ag1) # geometry same as pol
# works when x overlaps multiple objects in 'by':
p_buff = st_buffer(p, 0.2)
plot(p_buff, add = TRUE)
(p_ag2 = aggregate(p_buff, pol, mean)) # increased mean of second
# with nonmatching features
m3 = cbind(c(0, 0, 0.1, 0), c(0, 0.1, 0.1, 0))
pol = st_sfc(st_polygon(list(m3)), st_polygon(list(m1)), st_polygon(list(m2)))
(p_ag3 = aggregate(p, pol, mean))
plot(p_ag3)
# In case we need to pass an argument to the join function:
(p_ag4 = aggregate(p, pol, mean,
join = function(x, y) st_is_within_distance(x, y, dist = 0.3)))
Spatial*
and Spatial*DataFrame
objectsas_Spatial()
allows to convert sf
and sfc
to Spatial*DataFrame
and
Spatial*
for sp
compatibility. You can also use as(x, "Spatial")
To transform
sp
objects to sf
and sfc
with as(x, "sf")
.
as_Spatial(from, cast = TRUE, IDs = paste0("ID", seq_along(from)))
from 
object of class 
cast 
logical; if 
IDs 
character vector with IDs for the 
Package sp
supports three dimensions for POINT
and MULTIPOINT
(SpatialPoint*
).
Other geometries must be twodimensional (XY
). Dimensions can be dropped using
st_zm()
with what = "M"
or what = "ZM"
.
For converting simple features (i.e., sf
objects) to their Spatial
counterpart, use as(obj, "Spatial")
geometryonly object deriving from Spatial
, of the appropriate class
nc < st_read(system.file("shape/nc.shp", package="sf"))
if (require(sp, quietly = TRUE)) {
# convert to SpatialPolygonsDataFrame
spdf < as_Spatial(nc)
# identical to
spdf < as(nc, "Spatial")
# convert to SpatialPolygons
as(st_geometry(nc), "Spatial")
# back to sf
as(spdf, "sf")
}
Bind rows (features) of sf objects
Bind columns (variables) of sf objects
## S3 method for class 'sf'
rbind(..., deparse.level = 1)
## S3 method for class 'sf'
cbind(..., deparse.level = 1, sf_column_name = NULL)
st_bind_cols(...)
... 
objects to bind; note that for the rbind and cbind methods, all objects have to be of class 
deparse.level 
integer; see rbind 
sf_column_name 
character; specifies active geometry; passed on to st_sf 
both rbind
and cbind
have nonstandard method dispatch (see cbind): the rbind
or cbind
method for sf
objects is only called when all arguments to be binded are of class sf
.
If you need to cbind
e.g. a data.frame
to an sf
, use data.frame directly and use st_sf on its result, or use bind_cols; see examples.
st_bind_cols
is deprecated; use cbind
instead.
cbind
called with multiple sf
objects warns about multiple geometry columns present when the geometry column to use is not specified by using argument sf_column_name
; see also st_sf.
crs = st_crs(3857)
a = st_sf(a=1, geom = st_sfc(st_point(0:1)), crs = crs)
b = st_sf(a=1, geom = st_sfc(st_linestring(matrix(1:4,2))), crs = crs)
c = st_sf(a=4, geom = st_sfc(st_multilinestring(list(matrix(1:4,2)))), crs = crs)
rbind(a,b,c)
rbind(a,b)
rbind(a,b)
rbind(b,c)
cbind(a,b,c) # warns
if (require(dplyr, quietly = TRUE))
dplyr::bind_cols(a,b)
c = st_sf(a=4, geomc = st_sfc(st_multilinestring(list(matrix(1:4,2)))), crs = crs)
cbind(a,b,c, sf_column_name = "geomc")
df = data.frame(x=3)
st_sf(data.frame(c, df))
if (require(dplyr, quietly = TRUE))
dplyr::bind_cols(c, df)
TRUE
by defaultDrivers for which update should be TRUE
by default
db_drivers
An object of class character
of length 12.
Determine database type for R vector
Determine database type for R vector
## S4 method for signature 'PostgreSQLConnection,sf'
dbDataType(dbObj, obj)
## S4 method for signature 'DBIObject,sf'
dbDataType(dbObj, obj)
dbObj 
DBIObject driver or connection. 
obj 
Object to convert 
sf
object to DatabaseWrite sf
object to Database
Write sf
object to Database
## S4 method for signature 'PostgreSQLConnection,character,sf'
dbWriteTable(
conn,
name,
value,
...,
row.names = FALSE,
overwrite = FALSE,
append = FALSE,
field.types = NULL,
binary = TRUE
)
## S4 method for signature 'DBIObject,character,sf'
dbWriteTable(
conn,
name,
value,
...,
row.names = FALSE,
overwrite = FALSE,
append = FALSE,
field.types = NULL,
binary = TRUE
)
conn 
DBIObject 
name 
character vector of names (table names, fields, keywords). 
value 
a data.frame. 
... 
placeholder for future use. 
row.names 
Add a 
overwrite 
Will try to 
append 
Append rows to existing table; default 
field.types 
default 
binary 
Send geometries serialized as WellKnown Binary (WKB);
if 
Map extension to driver
extension_map
An object of class list
of length 26.
add or remove overviews to/from a raster image
gdal_addo(
file,
overviews = c(2, 4, 8, 16),
method = "NEAREST",
layers = integer(0),
options = character(0),
config_options = character(0),
clean = FALSE,
read_only = FALSE
)
file 
character; file name 
overviews 
integer; overview levels 
method 
character; method to create overview; one of: nearest, average, rms, gauss, cubic, cubicspline, lanczos, average_mp, average_magphase, mode 
layers 
integer; layers to create overviews for (default: all) 
options 
character; dataset opening options 
config_options 
named character vector with GDAL config options, like 
clean 
logical; if 
read_only 
logical; if 
TRUE
, invisibly, on success
gdal_utils for access to other gdal utilities that have a C API
Native interface to gdal utils
gdal_utils(
util = "info",
source,
destination,
options = character(0),
quiet = !(util %in% c("info", "gdalinfo", "ogrinfo", "vectorinfo", "mdiminfo")) 
("multi" %in% options),
processing = character(0),
colorfilename = character(0),
config_options = character(0)
)
util 
character; one of 
source 
character; name of input layer(s); for 
destination 
character; name of output layer 
options 
character; options for the utility 
quiet 
logical; if 
processing 
character; processing options for 
colorfilename 
character; name of color file for 
config_options 
named character vector with GDAL config options, like 
info
returns a character vector with the raster metadata; all other utils return (invisibly) a logical indicating success (i.e., TRUE
); in case of failure, an error is raised.
gdal_addo for adding overlays to a raste file; st_layers to query geometry type(s) and crs from layers in a (vector) data source
if (sf_extSoftVersion()["GDAL"] > "2.1.0") {
# info utils can be used to list information about about a raster
# dataset. More info: https://gdal.org/programs/ngdalinfo.html
in_file < system.file("tif/geomatrix.tif", package = "sf")
gdal_utils("info", in_file, options = c("mm", "proj4"))
# vectortranslate utils can be used to convert simple features data between
# file formats. More info: https://gdal.org/programs/ogr2ogr.html
in_file < system.file("shape/storms_xyz.shp", package="sf")
out_file < paste0(tempfile(), ".gpkg")
gdal_utils(
util = "vectortranslate",
source = in_file,
destination = out_file, # output format must be specified for GDAL < 2.3
options = c("f", "GPKG")
)
# The parameters can be specified as c("name") or c("name", "value"). The
# vectortranslate utils can perform also various operations during the
# conversion process. For example we can reproject the features during the
# translation.
gdal_utils(
util = "vectortranslate",
source = in_file,
destination = out_file,
options = c(
"f", "GPKG", # output file format for GDAL < 2.3
"s_srs", "EPSG:4326", # input file SRS
"t_srs", "EPSG:2264", # output file SRS
"overwrite"
)
)
st_read(out_file)
# The parameter s_srs had to be specified because, in this case, the in_file
# has no associated SRS.
st_read(in_file)
}
Perform geometric set operations with simple feature geometry collections
st_intersection(x, y, ...)
## S3 method for class 'sfc'
st_intersection(x, y, ...)
## S3 method for class 'sf'
st_intersection(x, y, ...)
st_difference(x, y, ...)
## S3 method for class 'sfc'
st_difference(x, y, ...)
st_sym_difference(x, y, ...)
st_snap(x, y, tolerance)
x 
object of class 
y 
object of class 
... 
arguments passed on to s2_options 
tolerance 
tolerance values used for 
When using GEOS and not using s2, a spatial index is built on argument x
; see https://rspatial.org/r/2017/06/22/spatialindex.html. The reference for the STR tree algorithm is: Leutenegger, Scott T., Mario A. Lopez, and Jeffrey Edgington. "STR: A simple and efficient algorithm for Rtree packing." Data Engineering, 1997. Proceedings. 13th international conference on. IEEE, 1997. For the pdf, search Google Scholar.
When called with missing y
, the sfc
method for st_intersection
returns all nonempty intersections of the geometries of x
; an attribute idx
contains a listcolumn with the indexes of contributing geometries.
when called with a missing y
, the sf
method for st_intersection
returns an sf
object with attributes taken from the contributing feature with lowest index; two fields are added: n.overlaps
with the number of overlapping features in x
, and a listcolumn origins
with indexes of all overlapping features.
When st_difference
is called with a single argument,
overlapping areas are erased from geometries that are indexed at greater
numbers in the argument to x
; geometries that are empty
or contained fully inside geometries with higher priority are removed entirely.
The st_difference.sfc
method with a single argument returns an object with
an "idx"
attribute with the original index for returned geometries.
st_snap
snaps the vertices and segments of a geometry to another geometry's vertices. If y
contains more than one geometry, its geometries are merged into a collection before snapping to that collection.
(from the GEOS docs:) "A snap distance tolerance is used to control where snapping is performed. Snapping one geometry to another can improve robustness for overlay operations by eliminating nearlycoincident edges (which cause problems during noding and intersection calculation). Too much snapping can result in invalid topology being created, so the number and location of snapped vertices is decided using heuristics to determine when it is safe to snap. This can result in some potential snaps being omitted, however."
The intersection, difference or symmetric difference between two sets of geometries.
The returned object has the same class as that of the first argument (x
) with the nonempty geometries resulting from applying the operation to all geometry pairs in x
and y
. In case x
is of class sf
, the matching attributes of the original object(s) are added. The sfc
geometry listcolumn returned carries an attribute idx
, which is an n
by2 matrix with every row the index of the corresponding entries of x
and y
, respectively.
To find whether pairs of simple feature geometries intersect, use
the function st_intersects
instead of st_intersection
.
When using GEOS and not using s2 polygons contain their boundary. When using s2 this is determined by the model
defaults of s2_options, which can be overridden via the ... argument, e.g. model = "closed"
to force DE9IM compliant behaviour of polygons (and reproduce GEOS results).
st_union for the union of simple features collections; intersect and setdiff for the base R set operations.
set.seed(131)
library(sf)
m = rbind(c(0,0), c(1,0), c(1,1), c(0,1), c(0,0))
p = st_polygon(list(m))
n = 100
l = vector("list", n)
for (i in 1:n)
l[[i]] = p + 10 * runif(2)
s = st_sfc(l)
plot(s, col = sf.colors(categorical = TRUE, alpha = .5))
title("overlapping squares")
d = st_difference(s) # sequential differences: s1, s2s1, s3s2s1, ...
plot(d, col = sf.colors(categorical = TRUE, alpha = .5))
title("nonoverlapping differences")
i = st_intersection(s) # all intersections
plot(i, col = sf.colors(categorical = TRUE, alpha = .5))
title("nonoverlapping intersections")
summary(lengths(st_overlaps(s, s))) # includes selfcounts!
summary(lengths(st_overlaps(d, d)))
summary(lengths(st_overlaps(i, i)))
sf = st_sf(s)
i = st_intersection(sf) # all intersections
plot(i["n.overlaps"])
summary(i$n.overlaps  lengths(i$origins))
# A helper function that erases all of y from x:
st_erase = function(x, y) st_difference(x, st_union(st_combine(y)))
poly = st_polygon(list(cbind(c(0, 0, 1, 1, 0), c(0, 1, 1, 0, 0))))
lines = st_multilinestring(list(
cbind(c(0, 1), c(1, 1.05)),
cbind(c(0, 1), c(0, .05)),
cbind(c(1, .95, 1), c(1.05, .5, .05))
))
snapped = st_snap(poly, lines, tolerance=.1)
plot(snapped, col='red')
plot(poly, border='green', add=TRUE)
plot(lines, lwd=2, col='blue', add=TRUE)
Geometric binary predicates on pairs of simple feature geometry sets
st_intersects(x, y, sparse = TRUE, ...)
st_disjoint(x, y = x, sparse = TRUE, prepared = TRUE)
st_touches(x, y, sparse = TRUE, prepared = TRUE, ...)
st_crosses(x, y, sparse = TRUE, prepared = TRUE, ...)
st_within(x, y, sparse = TRUE, prepared = TRUE, ...)
st_contains(x, y, sparse = TRUE, prepared = TRUE, ..., model = "open")
st_contains_properly(x, y, sparse = TRUE, prepared = TRUE, ...)
st_overlaps(x, y, sparse = TRUE, prepared = TRUE, ...)
st_equals(
x,
y,
sparse = TRUE,
prepared = FALSE,
...,
retain_unique = FALSE,
remove_self = FALSE
)
st_covers(x, y, sparse = TRUE, prepared = TRUE, ..., model = "closed")
st_covered_by(x, y = x, sparse = TRUE, prepared = TRUE, ..., model = "closed")
st_equals_exact(x, y, par, sparse = TRUE, prepared = FALSE, ...)
st_is_within_distance(x, y = x, dist, sparse = TRUE, ...)
x 
object of class 
y 
object of class 
sparse 
logical; should a sparse index list be returned ( 
... 
Arguments passed on to

prepared 
logical; prepare geometry for 
model 
character; polygon/polyline model; one of "open", "semiopen" or "closed"; see Details. 
retain_unique 
logical; if 
remove_self 
logical; if 
par 
numeric; parameter used for "equals_exact" (margin); 
dist 
distance threshold; geometry indexes with distances smaller or equal to this value are returned; numeric value or units value having distance units. 
If prepared
is TRUE
, and x
contains POINT geometries and y
contains polygons, then the polygon geometries are prepared, rather than the points.
For most predicates, a spatial index is built on argument x
; see https://rspatial.org/r/2017/06/22/spatialindex.html.
Specifically, st_intersects
, st_disjoint
, st_touches
st_crosses
, st_within
, st_contains
, st_contains_properly
, st_overlaps
, st_equals
, st_covers
and st_covered_by
all build spatial indexes for more efficient geometry calculations. st_relate
, st_equals_exact
, and do not; st_is_within_distance
uses a spatial index for geographic coordinates when sf_use_s2()
is true.
If y
is missing, st_predicate(x, x)
is effectively called, and a square matrix is returned with diagonal elements st_predicate(x[i], x[i])
.
Sparse geometry binary predicate (sgbp
) lists have the following attributes: region.id
with the row.names
of x
(if any, else 1:n
), ncol
with the number of features in y
, and predicate
with the name of the predicate used.
for model
, see https://github.com/rspatial/s2/issues/32
st_contains_properly(A,B)
is true if A intersects B's interior, but not its edges or exterior; A contains A, but A does not properly contain A.
See also st_relate and https://en.wikipedia.org/wiki/DE9IM for a more detailed description of the underlying algorithms.
st_equals_exact
returns true for two geometries of the same type and their vertices corresponding by index are equal up to a specified tolerance.
If sparse=FALSE
, st_predicate
(with predicate
e.g. "intersects") returns a dense logical matrix with element i,j
TRUE
when predicate(x[i], y[j])
(e.g., when geometry of feature i and j intersect); if sparse=TRUE
, an object of class sgbp
with a sparse list representation of the same matrix, with list element i
an integer vector with all indices j for which predicate(x[i],y[j])
is TRUE
(and hence a zerolength integer vector if none of them is TRUE
). From the dense matrix, one can find out if one or more elements intersect by apply(mat, 1, any)
, and from the sparse list by lengths(lst) > 0
, see examples below.
For intersection on pairs of simple feature geometries, use
the function st_intersection
instead of st_intersects
.
pts = st_sfc(st_point(c(.5,.5)), st_point(c(1.5, 1.5)), st_point(c(2.5, 2.5)))
pol = st_polygon(list(rbind(c(0,0), c(2,0), c(2,2), c(0,2), c(0,0))))
(lst = st_intersects(pts, pol))
(mat = st_intersects(pts, pol, sparse = FALSE))
# which points fall inside a polygon?
apply(mat, 1, any)
lengths(lst) > 0
# which points fall inside the first polygon?
st_intersects(pol, pts)[[1]]
# remove duplicate geometries:
p1 = st_point(0:1)
p2 = st_point(2:1)
p = st_sf(a = letters[1:8], geom = st_sfc(p1, p1, p2, p1, p1, p2, p2, p1))
st_equals(p)
st_equals(p, remove_self = TRUE)
(u = st_equals(p, retain_unique = TRUE))
# retain the records with unique geometries:
p[unlist(u),]
Combine several feature geometries into one, without unioning or resolving internal boundaries
st_combine(x)
st_union(x, y, ..., by_feature = FALSE, is_coverage = FALSE)
x 
object of class 
y 
object of class 
... 
ignored 
by_feature 
logical; if 
is_coverage 
logical; if 
st_combine
combines geometries without resolving borders, using c.sfg (analogous to c for ordinary vectors).
If st_union
is called with a single argument, x
, (with y
missing) and by_feature
is FALSE
all geometries are unioned together and an sfg
or singlegeometry sfc
object is returned.
If by_feature
is TRUE
each feature geometry is unioned individually.
This can for instance be used to resolve internal boundaries after polygons were combined using st_combine
.
If y
is provided, all elements of x
and y
are unioned, pairwise if by_feature
is TRUE, or else as the Cartesian product of both sets.
Unioning a set of overlapping polygons has the effect of merging the areas (i.e. the same effect as iteratively unioning all individual polygons together). Unioning a set of LineStrings has the effect of fully noding and dissolving the input linework. In this context "fully noded" means that there will be a node or endpoint in the output for every endpoint or line segment crossing in the input. "Dissolved" means that any duplicate (e.g. coincident) line segments or portions of line segments will be reduced to a single line segment in the output. Unioning a set of Points has the effect of merging all identical points (producing a set with no duplicates).
st_combine
returns a single, combined geometry, with no resolved boundaries; returned geometries may well be invalid.
If y
is missing, st_union(x)
returns a single geometry with resolved boundaries, else the geometries for all unioned pairs of x[i]
and y[j]
.
st_intersection, st_difference, st_sym_difference
nc = st_read(system.file("shape/nc.shp", package="sf"))
st_combine(nc)
plot(st_union(nc))
Compute Euclidean or great circle distance between pairs of geometries; compute, the area or the length of a set of geometries.
st_area(x, ...)
## S3 method for class 'sfc'
st_area(x, ...)
st_length(x, ...)
st_perimeter(x, ...)
st_distance(
x,
y,
...,
dist_fun,
by_element = FALSE,
which = ifelse(isTRUE(st_is_longlat(x)), "Great Circle", "Euclidean"),
par = 0,
tolerance = 0
)
x 
object of class 
... 
passed on to s2_distance, s2_distance_matrix, or s2_perimeter 
y 
object of class 
dist_fun 
deprecated 
by_element 
logical; if 
which 
character; for Cartesian coordinates only: one of 
par 
for 
tolerance 
ignored if 
great circle distance calculations use by default spherical distances (s2_distance or s2_distance_matrix); if sf_use_s2()
is FALSE
, ellipsoidal distances are computed using st_geod_distance which uses function geod_inverse
from GeographicLib (part of PROJ); see Karney, Charles FF, 2013, Algorithms for geodesics, Journal of Geodesy 87(1), 43–55
If the coordinate reference system of x
was set, these functions return values with unit of measurement; see set_units.
st_area returns the area of a geometry, in the coordinate reference system used; in case x
is in degrees longitude/latitude, st_geod_area is used for area calculation.
st_length returns the length of a LINESTRING
or MULTILINESTRING
geometry, using the coordinate reference system. POINT
, MULTIPOINT
, POLYGON
or MULTIPOLYGON
geometries return zero.
If by_element
is FALSE
st_distance
returns a dense numeric matrix of dimension length(x) by length(y); otherwise it returns a numeric vector the same length as x
and y
with an error raised if the lengths of x
and y
are unequal. Distances involving empty geometries are NA
.
st_dimension, st_cast to convert geometry types
b0 = st_polygon(list(rbind(c(1,1), c(1,1), c(1,1), c(1,1), c(1,1))))
b1 = b0 + 2
b2 = b0 + c(0.2, 2)
x = st_sfc(b0, b1, b2)
st_area(x)
line = st_sfc(st_linestring(rbind(c(30,30), c(40,40))), crs = 4326)
st_length(line)
outer = matrix(c(0,0,10,0,10,10,0,10,0,0),ncol=2, byrow=TRUE)
hole1 = matrix(c(1,1,1,2,2,2,2,1,1,1),ncol=2, byrow=TRUE)
hole2 = matrix(c(5,5,5,6,6,6,6,5,5,5),ncol=2, byrow=TRUE)
poly = st_polygon(list(outer, hole1, hole2))
mpoly = st_multipolygon(list(
list(outer, hole1, hole2),
list(outer + 12, hole1 + 12)
))
st_length(st_sfc(poly, mpoly))
st_perimeter(poly)
st_perimeter(mpoly)
p = st_sfc(st_point(c(0,0)), st_point(c(0,1)), st_point(c(0,2)))
st_distance(p, p)
st_distance(p, p, by_element = TRUE)
Dimension, simplicity, validity or is_empty queries on simple feature geometries
st_dimension(x, NA_if_empty = TRUE)
st_is_simple(x)
st_is_empty(x)
x 
object of class 
NA_if_empty 
logical; if TRUE, return NA for empty geometries 
st_dimension returns a numeric vector with 0 for points, 1 for lines, 2 for surfaces, and, if NA_if_empty
is TRUE
, NA
for empty geometries.
st_is_simple returns a logical vector, indicating for each geometry whether it is simple (e.g., not selfintersecting)
st_is_empty returns for each geometry whether it is empty
x = st_sfc(
st_point(0:1),
st_linestring(rbind(c(0,0),c(1,1))),
st_polygon(list(rbind(c(0,0),c(1,0),c(0,1),c(0,0)))),
st_multipoint(),
st_linestring(),
st_geometrycollection())
st_dimension(x)
st_dimension(x, FALSE)
ls = st_linestring(rbind(c(0,0), c(1,1), c(1,0), c(0,1)))
st_is_simple(st_sfc(ls, st_point(c(0,0))))
ls = st_linestring(rbind(c(0,0), c(1,1), c(1,0), c(0,1)))
st_is_empty(st_sfc(ls, st_point(), st_linestring()))
Geometric unary operations on simple feature geometries. These are all generics, with methods for sfg
, sfc
and sf
objects, returning an object of the same class. All operations work on a perfeature basis, ignoring all other features.
st_buffer(
x,
dist,
nQuadSegs = 30,
endCapStyle = "ROUND",
joinStyle = "ROUND",
mitreLimit = 1,
singleSide = FALSE,
...
)
st_boundary(x)
st_convex_hull(x)
st_concave_hull(x, ratio, ..., allow_holes)
st_simplify(x, preserveTopology, dTolerance = 0)
st_triangulate(x, dTolerance = 0, bOnlyEdges = FALSE)
st_triangulate_constrained(x)
st_inscribed_circle(x, dTolerance, ...)
st_minimum_rotated_rectangle(x, ...)
st_voronoi(x, envelope, dTolerance = 0, bOnlyEdges = FALSE)
st_polygonize(x)
st_line_merge(x, ..., directed = FALSE)
st_centroid(x, ..., of_largest_polygon = FALSE)
st_point_on_surface(x)
st_reverse(x)
st_node(x)
st_segmentize(x, dfMaxLength, ...)
x 
object of class 
dist 
numeric; buffer distance for all, or for each of the elements in 
nQuadSegs 
integer; number of segments per quadrant (fourth of a circle), for all or perfeature; see details 
endCapStyle 
character; style of line ends, one of 'ROUND', 'FLAT', 'SQUARE'; see details 
joinStyle 
character; style of line joins, one of 'ROUND', 'MITRE', 'BEVEL'; see details 
mitreLimit 
numeric; limit of extension for a join if 
singleSide 
logical; if 
... 
ignored 
ratio 
numeric; fraction convex: 1 returns the convex hulls, 0 maximally concave hulls 
allow_holes 
logical; if 
preserveTopology 
logical; carry out topology preserving
simplification? May be specified for each, or for all feature geometries.
Note that topology is preserved only for single feature geometries, not for
sets of them. If not specified (i.e. the default), then it is internally
set equal to 
dTolerance 
numeric; tolerance parameter, specified for all or for each
feature geometry. If you run 
bOnlyEdges 
logical; if TRUE, return lines, else return polygons 
envelope 
object of class 
directed 
logical; if 
of_largest_polygon 
logical; for 
dfMaxLength 
maximum length of a line segment. If 
st_buffer
computes a buffer around this geometry/each geometry. If any of endCapStyle
,
joinStyle
, or mitreLimit
are set to nondefault values ('ROUND', 'ROUND', 1.0 respectively) then
the underlying 'buffer with style' GEOS function is used.
If a negative buffer returns empty polygons instead of shrinking, set sf_use_s2() to FALSE
See postgis.net/docs/ST_Buffer.html for details.
nQuadSegs
, endCapsStyle
, joinStyle
, mitreLimit
and singleSide
only
work when the GEOS backend is used: for projected coordinates or when sf_use_s2()
is set
to FALSE
.
st_boundary
returns the boundary of a geometry
st_convex_hull
creates the convex hull of a set of points
st_concave_hull
creates the concave hull of a geometry
st_simplify
simplifies lines by removing vertices.
st_triangulate
triangulates set of points (not constrained). st_triangulate
requires GEOS version 3.4 or above
st_triangulate_constrained
returns the constrained delaunay triangulation of polygons; requires GEOS version 3.10 or above
st_inscribed_circle
returns the maximum inscribed circle for polygon geometries.
For st_inscribed_circle
, if nQuadSegs
is 0 a 2point LINESTRING is returned with the
center point and a boundary point of every circle, otherwise a circle (buffer) is returned where
nQuadSegs
controls the number of points per quadrant to approximate the circle.
st_inscribed_circle
requires GEOS version 3.9 or above
st_minimum_rotated_rectangle
returns the minimum
rotated rectangular POLYGON which encloses the input geometry. The
rectangle has width equal to the minimum diameter, and a longer
length. If the convex hill of the input is degenerate (a line or
point) a linestring or point is returned.
st_voronoi
creates voronoi tesselation. st_voronoi
requires GEOS version 3.5 or above
st_polygonize
creates polygon from lines that form a closed ring. In case of st_polygonize
, x
must be an object of class LINESTRING
or MULTILINESTRING
, or an sfc
geometry listcolumn object containing these
st_line_merge
merges lines. In case of st_line_merge
, x
must be an object of class MULTILINESTRING
, or an sfc
geometry listcolumn object containing these
st_centroid
gives the centroid of a geometry
st_point_on_surface
returns a point guaranteed to be on the (multi)surface.
st_reverse
reverses the nodes in a line
st_node
adds nodes to linear geometries at intersections without a node, and only works on individual linear geometries
st_segmentize
adds points to straight lines
an object of the same class of x
, with manipulated geometry.
chull for a more efficient algorithm for calculating the convex hull
## st_buffer, style options (taken from rgeos gBuffer)
l1 = st_as_sfc("LINESTRING(0 0,1 5,4 5,5 2,8 2,9 4,4 6.5)")
op = par(mfrow=c(2,3))
plot(st_buffer(l1, dist = 1, endCapStyle="ROUND"), reset = FALSE, main = "endCapStyle: ROUND")
plot(l1,col='blue',add=TRUE)
plot(st_buffer(l1, dist = 1, endCapStyle="FLAT"), reset = FALSE, main = "endCapStyle: FLAT")
plot(l1,col='blue',add=TRUE)
plot(st_buffer(l1, dist = 1, endCapStyle="SQUARE"), reset = FALSE, main = "endCapStyle: SQUARE")
plot(l1,col='blue',add=TRUE)
plot(st_buffer(l1, dist = 1, nQuadSegs=1), reset = FALSE, main = "nQuadSegs: 1")
plot(l1,col='blue',add=TRUE)
plot(st_buffer(l1, dist = 1, nQuadSegs=2), reset = FALSE, main = "nQuadSegs: 2")
plot(l1,col='blue',add=TRUE)
plot(st_buffer(l1, dist = 1, nQuadSegs= 5), reset = FALSE, main = "nQuadSegs: 5")
plot(l1,col='blue',add=TRUE)
par(op)
l2 = st_as_sfc("LINESTRING(0 0,1 5,3 2)")
op = par(mfrow = c(2, 3))
plot(st_buffer(l2, dist = 1, joinStyle="ROUND"), reset = FALSE, main = "joinStyle: ROUND")
plot(l2, col = 'blue', add = TRUE)
plot(st_buffer(l2, dist = 1, joinStyle="MITRE"), reset = FALSE, main = "joinStyle: MITRE")
plot(l2, col= 'blue', add = TRUE)
plot(st_buffer(l2, dist = 1, joinStyle="BEVEL"), reset = FALSE, main = "joinStyle: BEVEL")
plot(l2, col= 'blue', add=TRUE)
plot(st_buffer(l2, dist = 1, joinStyle="MITRE" , mitreLimit=0.5), reset = FALSE,
main = "mitreLimit: 0.5")
plot(l2, col = 'blue', add = TRUE)
plot(st_buffer(l2, dist = 1, joinStyle="MITRE",mitreLimit=1), reset = FALSE,
main = "mitreLimit: 1")
plot(l2, col = 'blue', add = TRUE)
plot(st_buffer(l2, dist = 1, joinStyle="MITRE",mitreLimit=3), reset = FALSE,
main = "mitreLimit: 3")
plot(l2, col = 'blue', add = TRUE)
par(op)
nc = st_read(system.file("shape/nc.shp", package="sf"))
nc_g = st_geometry(nc)
plot(st_convex_hull(nc_g))
plot(nc_g, border = grey(.5), add = TRUE)
pt = st_combine(st_sfc(st_point(c(0,80)), st_point(c(120,80)), st_point(c(240,80))))
st_convex_hull(pt) # R2
st_convex_hull(st_set_crs(pt, 'OGC:CRS84')) # S2
set.seed(131)
if (compareVersion(sf_extSoftVersion()[["GEOS"]], "3.11.0") > 1) {
pts = cbind(runif(100), runif(100))
m = st_multipoint(pts)
co = sf:::st_concave_hull(m, 0.3)
coh = sf:::st_concave_hull(m, 0.3, allow_holes = TRUE)
plot(co, col = 'grey')
plot(coh, add = TRUE, border = 'red')
plot(m, add = TRUE)
}
# st_simplify examples:
op = par(mfrow = c(2, 3), mar = rep(0, 4))
plot(nc_g[1])
plot(st_simplify(nc_g[1], dTolerance = 1e3)) # 1000m
plot(st_simplify(nc_g[1], dTolerance = 5e3)) # 5000m
nc_g_planar = st_transform(nc_g, 2264) # planar coordinates, US foot
plot(nc_g_planar[1])
plot(st_simplify(nc_g_planar[1], dTolerance = 1e3)) # 1000 foot
plot(st_simplify(nc_g_planar[1], dTolerance = 5e3)) # 5000 foot
par(op)
if (compareVersion(sf_extSoftVersion()[["GEOS"]], "3.10.0") > 1) {
pts = rbind(c(0,0), c(1,0), c(1,1), c(.5,.5), c(0,1), c(0,0))
po = st_polygon(list(pts))
co = st_triangulate_constrained(po)
tr = st_triangulate(po)
plot(po, col = NA, border = 'grey', lwd = 15)
plot(tr, border = 'green', col = NA, lwd = 5, add = TRUE)
plot(co, border = 'red', col = 'NA', add = TRUE)
}
if (compareVersion(sf_extSoftVersion()[["GEOS"]], "3.9.0") > 1) {
nc_t = st_transform(nc, 'EPSG:2264')
x = st_inscribed_circle(st_geometry(nc_t))
plot(st_geometry(nc_t), asp = 1, col = grey(.9))
plot(x, add = TRUE, col = '#ff9999')
}
set.seed(1)
x = st_multipoint(matrix(runif(10),,2))
box = st_polygon(list(rbind(c(0,0),c(1,0),c(1,1),c(0,1),c(0,0))))
if (compareVersion(sf_extSoftVersion()[["GEOS"]], "3.5.0") > 1) {
v = st_sfc(st_voronoi(x, st_sfc(box)))
plot(v, col = 0, border = 1, axes = TRUE)
plot(box, add = TRUE, col = 0, border = 1) # a larger box is returned, as documented
plot(x, add = TRUE, col = 'red', cex=2, pch=16)
plot(st_intersection(st_cast(v), box)) # clip to smaller box
plot(x, add = TRUE, col = 'red', cex=2, pch=16)
# matching Voronoi polygons to data points:
# https://github.com/rspatial/sf/issues/1030
# generate 50 random unif points:
n = 100
pts = st_as_sf(data.frame(matrix(runif(n), , 2), id = 1:(n/2)), coords = c("X1", "X2"))
# compute Voronoi polygons:
pols = st_collection_extract(st_voronoi(do.call(c, st_geometry(pts))))
# match them to points:
pts$pols = pols[unlist(st_intersects(pts, pols))]
plot(pts["id"], pch = 16) # ID is color
plot(st_set_geometry(pts, "pols")["id"], xlim = c(0,1), ylim = c(0,1), reset = FALSE)
plot(st_geometry(pts), add = TRUE)
layout(matrix(1)) # reset plot layout
}
mls = st_multilinestring(list(matrix(c(0,0,0,1,1,1,0,0),,2,byrow=TRUE)))
st_polygonize(st_sfc(mls))
mls = st_multilinestring(list(rbind(c(0,0), c(1,1)), rbind(c(2,0), c(1,1))))
st_line_merge(st_sfc(mls))
plot(nc_g, axes = TRUE)
plot(st_centroid(nc_g), add = TRUE, pch = 3, col = 'red')
mp = st_combine(st_buffer(st_sfc(lapply(1:3, function(x) st_point(c(x,x)))), 0.2 * 1:3))
plot(mp)
plot(st_centroid(mp), add = TRUE, col = 'red') # centroid of combined geometry
plot(st_centroid(mp, of_largest_polygon = TRUE), add = TRUE, col = 'blue', pch = 3)
plot(nc_g, axes = TRUE)
plot(st_point_on_surface(nc_g), add = TRUE, pch = 3, col = 'red')
if (compareVersion(sf_extSoftVersion()[["GEOS"]], "3.7.0") > 1) {
st_reverse(st_linestring(rbind(c(1,1), c(2,2), c(3,3))))
}
(l = st_linestring(rbind(c(0,0), c(1,1), c(0,1), c(1,0), c(0,0))))
st_polygonize(st_node(l))
st_node(st_multilinestring(list(rbind(c(0,0), c(1,1), c(0,1), c(1,0), c(0,0)))))
sf = st_sf(a=1, geom=st_sfc(st_linestring(rbind(c(0,0),c(1,1)))), crs = 4326)
if (require(lwgeom, quietly = TRUE)) {
seg = st_segmentize(sf, units::set_units(100, km))
seg = st_segmentize(sf, units::set_units(0.01, rad))
nrow(seg$geom[[1]])
}
Arealweighted interpolation of polygon data
st_interpolate_aw(x, to, extensive, ...)
## S3 method for class 'sf'
st_interpolate_aw(x, to, extensive, ..., keep_NA = FALSE)
x 
object of class 
to 
object of class 
extensive 
logical; if TRUE, the attribute variables are assumed to be spatially extensive (like population) and the sum is preserved, otherwise, spatially intensive (like population density) and the mean is preserved. 
... 
ignored 
keep_NA 
logical; if 
nc = st_read(system.file("shape/nc.shp", package="sf"))
g = st_make_grid(nc, n = c(10, 5))
a1 = st_interpolate_aw(nc["BIR74"], g, extensive = FALSE)
sum(a1$BIR74) / sum(nc$BIR74) # not close to one: property is assumed spatially intensive
a2 = st_interpolate_aw(nc["BIR74"], g, extensive = TRUE)
# verify mass preservation (pycnophylactic) property:
sum(a2$BIR74) / sum(nc$BIR74)
a1$intensive = a1$BIR74
a1$extensive = a2$BIR74
plot(a1[c("intensive", "extensive")], key.pos = 4)
Search through the driver table if driver is listed
is_driver_available(drv, drivers = st_drivers())
drv 
character. Name of driver 
drivers 
data.frame. Table containing driver names and support. Default
is from 
Search through the driver table to match a driver name with
an action (e.g. "write"
) and check if the action is supported.
is_driver_can(drv, drivers = st_drivers(), operation = "write")
drv 
character. Name of driver 
drivers 
data.frame. Table containing driver names and support. Default
is from 
operation 
character. What action to check 
Check if the columns could be of a coercable type for sf
is_geometry_column(con, x, classes = "")
con 
database connection 
x 
inherits data.frame 
classes 
classes inherited 
merge method for sf and data.frame object
## S3 method for class 'sf'
merge(x, y, ...)
x 
object of class 
y 
object of class 
... 
arguments passed on to 
a = data.frame(a = 1:3, b = 5:7)
st_geometry(a) = st_sfc(st_point(c(0,0)), st_point(c(1,1)), st_point(c(2,2)))
b = data.frame(x = c("a", "b", "c"), b = c(2,5,6))
merge(a, b)
merge(a, b, all = TRUE)
Sudden Infant Death Syndrome (SIDS) sample data for North Carolina counties,
two time periods (197478 and 197984). The details of the columns can be
found in a spdep package vignette.
Please note that, though this is basically the same as nc.sids
dataset in spData
package, nc
only contains a subset of variables. The differences are
also discussed on the vignette.
A sf
object
https://rspatial.github.io/spdep/articles/sids.html
nc < st_read(system.file("shape/nc.shp", package="sf"))
Arithmetic operators for simple feature geometries
## S3 method for class 'sfg'
Ops(e1, e2)
## S3 method for class 'sfc'
Ops(e1, e2)
e1 
object of class 
e2 
numeric, or object of class 
in case e2
is numeric, +, , *, /, %% and %/% add, subtract, multiply, divide, modulo, or integerdivide by e2
. In case e2
is an n x n matrix, * matrixmultiplies and / multiplies by its inverse. If e2
is an sfg
object, , /, & and %/% result in the geometric union, difference, intersection and symmetric difference respectively, and ==
and !=
return geometric (in)equality, using st_equals. If e2
is an sfg
or sfc
object, for operations +
and 
it has to have POINT
geometries.
If e1
is of class sfc
, and e2
is a length 2 numeric, then it is considered a twodimensional point (and if needed repeated as such) only for operations +
and 
, in other cases the individual numbers are repeated; see commented examples.
It has been reported (https://github.com/rspatial/sf/issues/2067) that certain ATLAS versions result in invalid polygons, where the final point in a ring is no longer equal to the first point. In that case, setting the precisions with st_set_precision may help.
object of class sfg
st_point(c(1,2,3)) + 4
st_point(c(1,2,3)) * 3 + 4
m = matrix(0, 2, 2)
diag(m) = c(1, 3)
# affine:
st_point(c(1,2)) * m + c(2,5)
# world in 0360 range:
if (require(maps, quietly = TRUE)) {
w = st_as_sf(map('world', plot = FALSE, fill = TRUE))
w2 = (st_geometry(w) + c(360,90)) %% c(360)  c(0,90)
w3 = st_wrap_dateline(st_set_crs(w2  c(180,0), 4326)) + c(180,0)
plot(st_set_crs(w3, 4326), axes = TRUE)
}
(mp < st_point(c(1,2)) + st_point(c(3,4))) # MULTIPOINT (1 2, 3 4)
mp  st_point(c(3,4)) # POINT (1 2)
opar = par(mfrow = c(2,2), mar = c(0, 0, 1, 0))
a = st_buffer(st_point(c(0,0)), 2)
b = a + c(2, 0)
p = function(m) { plot(c(a,b)); plot(eval(parse(text=m)), col=grey(.9), add = TRUE); title(m) }
o = lapply(c('a  b', 'a / b', 'a & b', 'a %/% b'), p)
par(opar)
sfc = st_sfc(st_point(0:1), st_point(2:3))
sfc + c(2,3) # added to EACH geometry
sfc * c(2,3) # first geometry multiplied by 2, second by 3
nc = st_transform(st_read(system.file("gpkg/nc.gpkg", package="sf")), 32119) # nc state plane, m
b = st_buffer(st_centroid(st_union(nc)), units::set_units(50, km)) # shoot a hole in nc:
plot(st_geometry(nc) / b, col = grey(.9))
plot one or more attributes of an sf object on a map Plot sf object
## S3 method for class 'sf'
plot(
x,
y,
...,
main,
pal = NULL,
nbreaks = 10,
breaks = "pretty",
max.plot = getOption("sf_max.plot", default = 9),
key.pos = get_key_pos(x, ...),
key.length = 0.618,
key.width = kw_dflt(x, key.pos),
reset = TRUE,
logz = FALSE,
extent = x,
xlim = st_bbox(extent)[c(1, 3)],
ylim = st_bbox(extent)[c(2, 4)],
compact = FALSE
)
get_key_pos(x, ...)
## S3 method for class 'sfc_POINT'
plot(
x,
y,
...,
pch = 1,
cex = 1,
col = 1,
bg = 0,
lwd = 1,
lty = 1,
type = "p",
add = FALSE
)
## S3 method for class 'sfc_MULTIPOINT'
plot(
x,
y,
...,
pch = 1,
cex = 1,
col = 1,
bg = 0,
lwd = 1,
lty = 1,
type = "p",
add = FALSE
)
## S3 method for class 'sfc_LINESTRING'
plot(x, y, ..., lty = 1, lwd = 1, col = 1, pch = 1, type = "l", add = FALSE)
## S3 method for class 'sfc_CIRCULARSTRING'
plot(x, y, ...)
## S3 method for class 'sfc_MULTILINESTRING'
plot(x, y, ..., lty = 1, lwd = 1, col = 1, pch = 1, type = "l", add = FALSE)
## S3 method for class 'sfc_POLYGON'
plot(
x,
y,
...,
lty = 1,
lwd = 1,
col = NA,
cex = 1,
pch = NA,
border = 1,
add = FALSE,
rule = "evenodd",
xpd = par("xpd")
)
## S3 method for class 'sfc_MULTIPOLYGON'
plot(
x,
y,
...,
lty = 1,
lwd = 1,
col = NA,
border = 1,
add = FALSE,
rule = "evenodd",
xpd = par("xpd")
)
## S3 method for class 'sfc_GEOMETRYCOLLECTION'
plot(
x,
y,
...,
pch = 1,
cex = 1,
bg = 0,
lty = 1,
lwd = 1,
col = 1,
border = 1,
add = FALSE
)
## S3 method for class 'sfc_GEOMETRY'
plot(
x,
y,
...,
pch = 1,
cex = 1,
bg = 0,
lty = 1,
lwd = 1,
col = ifelse(st_dimension(x) == 2, NA, 1),
border = 1,
add = FALSE
)
## S3 method for class 'sfg'
plot(x, ...)
plot_sf(
x,
xlim = NULL,
ylim = NULL,
asp = NA,
axes = FALSE,
bgc = par("bg"),
...,
xaxs,
yaxs,
lab,
setParUsrBB = FALSE,
bgMap = NULL,
expandBB = c(0, 0, 0, 0),
graticule = NA_crs_,
col_graticule = "grey",
border,
extent = x
)
sf.colors(n = 10, cutoff.tails = c(0.35, 0.2), alpha = 1, categorical = FALSE)
x 
object of class sf 
y 
ignored 
... 

main 
title for plot ( 
pal 
palette function, similar to rainbow, or palette values; if omitted, 
nbreaks 
number of colors breaks (ignored for 
breaks 
either a numeric vector with the actual breaks, or a name of a method accepted by the 
max.plot 
integer; lower boundary to maximum number of attributes to plot; the default value (9) can be overridden by setting the global option 
key.pos 
numeric; side to plot a color key: 1 bottom, 2 left, 3 top, 4 right; set to 
key.length 
amount of space reserved for the key along its axis, length of the scale bar 
key.width 
amount of space reserved for the key (incl. labels), thickness/width of the scale bar 
reset 
logical; if 
logz 
logical; if 
extent 
object with an 
xlim 
see plot.window 
ylim 
see plot.window 
compact 
logical; compact subplots over plotting space? 
pch 
plotting symbol 
cex 
symbol size 
col 
color for plotting features; if 
bg 
symbol background color 
lwd 
line width 
lty 
line type 
type 
plot type: 'p' for points, 'l' for lines, 'b' for both 
add 
logical; add to current plot? Note that when using 
border 
color of polygon border(s); using 
rule 
see polypath; for 
xpd 
see par; sets polygon clipping strategy; only implemented for POLYGON and MULTIPOLYGON 
asp 
see below, and see par 
axes 
logical; should axes be plotted? (default FALSE) 
bgc 
background color 
xaxs 
see par 
yaxs 
see par 
lab 
see par 
setParUsrBB 
default FALSE; set the 
bgMap 
object of class 
expandBB 
numeric; fractional values to expand the bounding box with, in each direction (bottom, left, top, right) 
graticule 
logical, or object of class 
col_graticule 
color to used for the graticule (if present) 
n 
integer; number of colors 
cutoff.tails 
numeric, in 
alpha 
numeric, in 
categorical 
logical; do we want colors for a categorical variable? (see details) 
plot.sf
maximally plots max.plot
maps with colors following from attribute columns,
one map per attribute. It uses sf.colors
for default colors. For more control over placement of individual maps,
set parameter mfrow
with par prior to plotting, and plot single maps one by one; note that this only works
in combination with setting parameters key.pos=NULL
(no legend) and reset=FALSE
.
plot.sfc
plots the geometry, additional parameters can be passed on
to control color, lines or symbols.
When setting reset
to FALSE
, the original device parameters are lost, and the device must be reset using dev.off()
in order to reset it.
parameter at
can be set to specify where labels are placed along the key; see examples.
The features are plotted in the order as they apppear in the sf object. See examples for when a different plotting order is wanted.
plot_sf
sets up the plotting area, axes, graticule, or webmap background; it
is called by all plot
methods before anything is drawn.
The argument setParUsrBB
may be used to pass the logical value TRUE
to functions within plot.Spatial
. When set to TRUE
, par(“usr”) will be overwritten with c(xlim, ylim)
, which defaults to the bounding box of the spatial object. This is only needed in the particular context of graphic output to a specified device with given width and height, to be matched to the spatial object, when using par(“xaxs”) and par(“yaxs”) in addition to par(mar=c(0,0,0,0))
.
The default aspect for map plots is 1; if however data are not
projected (coordinates are long/lat), the aspect is by default set to
1/cos(My * pi/180) with My the y coordinate of the middle of the map
(the mean of ylim
, which defaults to the y range of bounding box). This
implies an Equirectangular projection.
noncategorical colors from sf.colors
were taken from bpy.colors, with modified cutoff.tails
defaults
If categorical is TRUE
, default colors are from https://colorbrewer2.org/ (if n < 9, Set2, else Set3).
nc = st_read(system.file("gpkg/nc.gpkg", package="sf"), quiet = TRUE)
# plot single attribute, autolegend:
plot(nc["SID74"])
# plot multiple:
plot(nc[c("SID74", "SID79")]) # better use ggplot2::geom_sf to facet and get a single legend!
# adding to a plot of an sf object only works when using reset=FALSE in the first plot:
plot(nc["SID74"], reset = FALSE)
plot(st_centroid(st_geometry(nc)), add = TRUE)
# log10 zscale:
plot(nc["SID74"], logz = TRUE, breaks = c(0,.5,1,1.5,2), at = c(0,.5,1,1.5,2))
# and we need to reset the plotting device after that, e.g. by
layout(1)
# when plotting only geometries, the reset=FALSE is not needed:
plot(st_geometry(nc))
plot(st_geometry(nc)[1], col = 'red', add = TRUE)
# add a custom legend to an arbitray plot:
layout(matrix(1:2, ncol = 2), widths = c(1, lcm(2)))
plot(1)
.image_scale(1:10, col = sf.colors(9), key.length = lcm(8), key.pos = 4, at = 1:10)
# manipulate plotting order, plot largest polygons first:
p = st_polygon(list(rbind(c(0,0), c(1,0), c(1,1), c(0,1), c(0,0))))
x = st_sf(a=1:4, st_sfc(p, p * 2, p * 3, p * 4)) # plot(x, col=2:5) only shows the largest polygon!
plot(x[order(st_area(x), decreasing = TRUE),], col = 2:5) # plot largest polygons first
sf.colors(10)
Map prefix to driver
prefix_map
An object of class list
of length 10.
Query or manage PROJ search path and network settings
sf_proj_search_paths(paths = character(0), with_proj = NA)
sf_proj_network(enable = FALSE, url = character(0))
sf_proj_pipelines(
source_crs,
target_crs,
authority = character(0),
AOI = numeric(0),
Use = "NONE",
grid_availability = "USED",
desired_accuracy = 1,
strict_containment = FALSE,
axis_order_authority_compliant = st_axis_order()
)
paths 
the search path to be set; omit if paths need to be queried 
with_proj 
logical; if 
enable 
logical; set this to enable ( 
url 
character; use this to specify and override the default proj network CDN 
source_crs , target_crs

object of class 
authority 
character; constrain output pipelines to those of authority 
AOI 
length four numeric; desired area of interest for the resulting coordinate transformations (west, south, east, north, in degrees). For an area of interest crossing the antimeridian, west will be greater than east. 
Use 
one of "NONE", "BOTH", "INTERSECTION", "SMALLEST", indicating how AOI's of source_crs and target_crs are being used 
grid_availability 
character; one of "USED" (Grid availability is only used for sorting results. Operations where some grids are missing will be sorted last), "DISCARD" (Completely discard an operation if a required grid is missing) , "IGNORED" (Ignore grid availability at all. Results will be presented as if all grids were available.), or "AVAILABLE" (Results will be presented as if grids known to PROJ (that is registered in the grid_alternatives table of its database) were available. Used typically when networking is enabled.) 
desired_accuracy 
numeric; only return pipelines with at least this accuracy 
strict_containment 
logical; default 
axis_order_authority_compliant 
logical; if 
sf_proj_search_paths()
returns the search path (possibly after setting it)
sf_proj_network
when called without arguments returns a logical indicating whether
network search of datum grids is enabled, when called with arguments it returns a character
vector with the URL of the CDN used (or specified with url
).
sf_proj_pipelines()
returns a table with candidate coordinate transformation
pipelines along with their accuracy; NA
accuracy indicates ballpark accuracy.
Convert raw vector(s) into hexadecimal character string(s)
rawToHex(x)
x 
raw vector, or list with raw vectors 
functions for spherical geometry, using the s2 package based on the google s2geometry.io library
sf_use_s2(use_s2)
st_as_s2(x, ...)
## S3 method for class 'sf'
st_as_s2(x, ...)
## S3 method for class 'sfc'
st_as_s2(x, ..., oriented = getOption("s2_oriented", FALSE), rebuild = FALSE)
use_s2 
logical; if 
x 
object of class 
... 
passed on 
oriented 
logical; if 
rebuild 
logical; call s2_rebuild on the geometry (think of this as a 
st_as_s2
converts an sf
POLYGON object into a form readable by s2
.
sf_use_s2
returns the value of this variable before (re)setting it,
invisibly if use_s2
is not missing.
m = rbind(c(1,1), c(1,1), c(1,1), c(1,1), c(1,1))
m1 = rbind(c(1,1), c(1,1), c(1,1), c(1,1), c(1,0), c(1,1))
m0 = m[5:1,]
mp = st_multipolygon(list(
list(m, 0.8 * m0, 0.01 * m1 + 0.9),
list(0.7* m, 0.6*m0),
list(0.5 * m0),
list(m+2),
list(m+4,(.9*m0)+4)
))
sf = st_sfc(mp, mp, crs = 'EPSG:4326')
s2 = st_as_s2(sf)
Create sf, which extends data.framelike objects with a simple feature list column.
To convert a data frame object to sf
, use st_as_sf()
st_sf(
...,
agr = NA_agr_,
row.names,
stringsAsFactors = sf_stringsAsFactors(),
crs,
precision,
sf_column_name = NULL,
check_ring_dir = FALSE,
sfc_last = TRUE
)
## S3 method for class 'sf'
x[i, j, ..., drop = FALSE, op = st_intersects]
## S3 method for class 'sf'
print(x, ..., n = getOption("sf_max_print", default = 10))
... 
column elements to be binded into an 
agr 
character vector; see details below. 
row.names 
row.names for the created 
stringsAsFactors 
logical; see st_read 
crs 
coordinate reference system, something suitable as input to st_crs 
precision 
numeric; see st_as_binary 
sf_column_name 
character; name of the active listcolumn with simple feature geometries; in case
there is more than one and 
check_ring_dir 
see st_read 
sfc_last 
logical; if 
x 
object of class 
i 
record selection, see [.data.frame, or a 
j 
variable selection, see [.data.frame 
drop 
logical, default 
op 
function; geometrical binary predicate function to apply when 
n 
maximum number of features to print; can be set globally by 
agr
, attributegeometryrelationship, specifies for each nongeometry attribute column how it relates to the geometry, and can have one of following values: "constant", "aggregate", "identity". "constant" is used for attributes that are constant throughout the geometry (e.g. land use), "aggregate" where the attribute is an aggregate value over the geometry (e.g. population density or population count), "identity" when the attributes uniquely identifies the geometry of particular "thing", such as a building ID or a city name. The default value, NA_agr_
, implies we don't know.
When a single value is provided to agr
, it is cascaded across all input columns; otherwise, a named vector like c(feature1='constant', ...)
will set agr
value to 'constant'
for the input column named feature1
. See demo(nc)
for a worked example of this.
When confronted with a data.framelike object, st_sf
will try to find a geometry column of class sfc
, and otherwise try to convert listcolumns when available into a geometry column, using st_as_sfc.
[.sf
will return a data.frame
or vector if the geometry column (of class sfc
) is dropped (drop=TRUE
), an sfc
object if only the geometry column is selected, and otherwise return an sf
object; see also [.data.frame; for [.sf
...
arguments are passed to op
.
g = st_sfc(st_point(1:2))
st_sf(a=3,g)
st_sf(g, a=3)
st_sf(a=3, st_sfc(st_point(1:2))) # better to name it!
# create empty structure with preallocated empty geometries:
nrows < 10
geometry = st_sfc(lapply(1:nrows, function(x) st_geometrycollection()))
df < st_sf(id = 1:nrows, geometry = geometry)
g = st_sfc(st_point(1:2), st_point(3:4))
s = st_sf(a=3:4, g)
s[1,]
class(s[1,])
s[,1]
class(s[,1])
s[,2]
class(s[,2])
g = st_sf(a=2:3, g)
pol = st_sfc(st_polygon(list(cbind(c(0,3,3,0,0),c(0,0,3,3,0)))))
h = st_sf(r = 5, pol)
g[h,]
h[g,]
Provide the external dependencies versions of the libraries linked to sf
sf_extSoftVersion()
directly transform a set of coordinates
sf_add_proj_units()
sf_project(
from = character(0),
to = character(0),
pts,
keep = FALSE,
warn = TRUE,
authority_compliant = st_axis_order()
)
from 
character description of source CRS, or object of class 
to 
character description of target CRS, or object of class 
pts 
two, three or fourcolumn numeric matrix, or object that can be coerced into a matrix; columns 3 and 4 contain z and t values. 
keep 
logical value controlling the handling of unprojectable points. If

warn 
logical; if 
authority_compliant 
logical; 
sf_add_proj_units
loads the PROJ units link
, us_in
, ind_yd
, ind_ft
, and ind_ch
into the udunits database, and returns TRUE
invisibly on success.
twocolumn numeric matrix with transformed/converted coordinates, returning invalid values as Inf
sf_add_proj_units()
Create simple feature geometry list column, set class, and add coordinate reference system and precision.
For data.frame alternatives see st_sf()
. To convert a foreign object to sfc
, see st_as_sfc()
st_sfc(
...,
crs = NA_crs_,
precision = 0,
check_ring_dir = FALSE,
dim,
recompute_bbox = FALSE
)
## S3 method for class 'sfc'
x[i, j, ..., op = st_intersects]
... 
zero or more simple feature geometries (objects of class 
crs 
coordinate reference system: integer with the EPSG code, or character with proj4string 
precision 
numeric; see st_as_binary 
check_ring_dir 
see st_read 
dim 
character; if this function is called without valid geometries, this argument may carry the right dimension to set empty geometries 
recompute_bbox 
logical; use 
x 
object of class 
i 
record selection. Might also be an 
j 
ignored 
op 
function, geometrical binary predicate function to apply when

A simple feature geometry listcolumn is a list of class
c("stc_TYPE", "sfc")
which most often contains objects of identical type;
in case of a mix of types or an empty set, TYPE
is set to the
superclass GEOMETRY
.
an object of class sfc
, which is a classed listcolumn with simple feature geometries.
pt1 = st_point(c(0,1))
pt2 = st_point(c(1,1))
(sfc = st_sfc(pt1, pt2))
sfc[sfc[1], op = st_is_within_distance, dist = 0.5]
d = st_sf(data.frame(a=1:2, geom=sfc))
Methods for dealing with sparse geometry binary predicate lists
## S3 method for class 'sgbp'
print(x, ..., n = 10, max_nb = 10)
## S3 method for class 'sgbp'
t(x)
## S3 method for class 'sgbp'
as.matrix(x, ...)
## S3 method for class 'sgbp'
dim(x)
x 
object of class 
... 
ignored 
n 
integer; maximum number of items to print 
max_nb 
integer; maximum number of neighbours to print for each item 
sgbp
are sparse matrices, stored as a list with integer vectors holding the ordered TRUE
indices of each row. This means that for a dense, $m \times n$
matrix Q
and a list L
, if Q[i,j]
is TRUE
then $j$
is an element of L[[i]]
. Reversed: when $k$
is the value of L[[i]][j]
, then Q[i,k]
is TRUE
.
Create simple feature from a numeric vector, matrix or list
st_point(x = c(NA_real_, NA_real_), dim = "XYZ")
st_multipoint(x = matrix(numeric(0), 0, 2), dim = "XYZ")
st_linestring(x = matrix(numeric(0), 0, 2), dim = "XYZ")
st_polygon(x = list(), dim = if (length(x)) "XYZ" else "XY")
st_multilinestring(x = list(), dim = if (length(x)) "XYZ" else "XY")
st_multipolygon(x = list(), dim = if (length(x)) "XYZ" else "XY")
st_geometrycollection(x = list(), dims = "XY")
## S3 method for class 'sfg'
print(x, ..., width = 0)
## S3 method for class 'sfg'
head(x, n = 10L, ...)
## S3 method for class 'sfg'
format(x, ..., width = 30)
## S3 method for class 'sfg'
c(..., recursive = FALSE, flatten = TRUE)
## S3 method for class 'sfg'
as.matrix(x, ...)
x 
for 
dim 
character, indicating dimensions: "XY", "XYZ", "XYM", or "XYZM"; only really needed for threedimensional points (which can be either XYZ or XYM) or empty geometries; see details 
dims 
character; specify dimensionality in case of an empty (NULL) geometrycollection, in which case 
... 
objects to be pasted together into a single simple feature 
width 
integer; number of characters to be printed (max 30; 0 means print everything) 
n 
integer; number of elements to be selected 
recursive 
logical; ignored 
flatten 
logical; if 
"XYZ" refers to coordinates where the third dimension represents altitude, "XYM" refers to threedimensional coordinates where the third dimension refers to something else ("M" for measure); checking of the sanity of x
may be only partial.
When flatten=TRUE
, this method may merge points into a multipoint structure, and may not preserve order, and hence cannot be reverted. When given fish, it returns fish soup.
object of the same nature as x
, but with appropriate class attribute set
as.matrix returns the set of points that form a geometry as a single matrix, where each point is a row; use unlist(x, recursive = FALSE)
to get sets of matrices.
(p1 = st_point(c(1,2)))
class(p1)
st_bbox(p1)
(p2 = st_point(c(1,2,3)))
class(p2)
(p3 = st_point(c(1,2,3), "XYM"))
pts = matrix(1:10, , 2)
(mp1 = st_multipoint(pts))
pts = matrix(1:15, , 3)
(mp2 = st_multipoint(pts))
(mp3 = st_multipoint(pts, "XYM"))
pts = matrix(1:20, , 4)
(mp4 = st_multipoint(pts))
pts = matrix(1:10, , 2)
(ls1 = st_linestring(pts))
pts = matrix(1:15, , 3)
(ls2 = st_linestring(pts))
(ls3 = st_linestring(pts, "XYM"))
pts = matrix(1:20, , 4)
(ls4 = st_linestring(pts))
outer = matrix(c(0,0,10,0,10,10,0,10,0,0),ncol=2, byrow=TRUE)
hole1 = matrix(c(1,1,1,2,2,2,2,1,1,1),ncol=2, byrow=TRUE)
hole2 = matrix(c(5,5,5,6,6,6,6,5,5,5),ncol=2, byrow=TRUE)
pts = list(outer, hole1, hole2)
(ml1 = st_multilinestring(pts))
pts3 = lapply(pts, function(x) cbind(x, 0))
(ml2 = st_multilinestring(pts3))
(ml3 = st_multilinestring(pts3, "XYM"))
pts4 = lapply(pts3, function(x) cbind(x, 0))
(ml4 = st_multilinestring(pts4))
outer = matrix(c(0,0,10,0,10,10,0,10,0,0),ncol=2, byrow=TRUE)
hole1 = matrix(c(1,1,1,2,2,2,2,1,1,1),ncol=2, byrow=TRUE)
hole2 = matrix(c(5,5,5,6,6,6,6,5,5,5),ncol=2, byrow=TRUE)
pts = list(outer, hole1, hole2)
(pl1 = st_polygon(pts))
pts3 = lapply(pts, function(x) cbind(x, 0))
(pl2 = st_polygon(pts3))
(pl3 = st_polygon(pts3, "XYM"))
pts4 = lapply(pts3, function(x) cbind(x, 0))
(pl4 = st_polygon(pts4))
pol1 = list(outer, hole1, hole2)
pol2 = list(outer + 12, hole1 + 12)
pol3 = list(outer + 24)
mp = list(pol1,pol2,pol3)
(mp1 = st_multipolygon(mp))
pts3 = lapply(mp, function(x) lapply(x, function(y) cbind(y, 0)))
(mp2 = st_multipolygon(pts3))
(mp3 = st_multipolygon(pts3, "XYM"))
pts4 = lapply(mp2, function(x) lapply(x, function(y) cbind(y, 0)))
(mp4 = st_multipolygon(pts4))
(gc = st_geometrycollection(list(p1, ls1, pl1, mp1)))
st_geometrycollection() # empty geometry
c(st_point(1:2), st_point(5:6))
c(st_point(1:2), st_multipoint(matrix(5:8,2)))
c(st_multipoint(matrix(1:4,2)), st_multipoint(matrix(5:8,2)))
c(st_linestring(matrix(1:6,3)), st_linestring(matrix(11:16,3)))
c(st_multilinestring(list(matrix(1:6,3))), st_multilinestring(list(matrix(11:16,3))))
pl = list(rbind(c(0,0), c(1,0), c(1,1), c(0,1), c(0,0)))
c(st_polygon(pl), st_polygon(pl))
c(st_polygon(pl), st_multipolygon(list(pl)))
c(st_linestring(matrix(1:6,3)), st_point(1:2))
c(st_geometrycollection(list(st_point(1:2), st_linestring(matrix(1:6,3)))),
st_geometrycollection(list(st_multilinestring(list(matrix(11:16,3))))))
c(st_geometrycollection(list(st_point(1:2), st_linestring(matrix(1:6,3)))),
st_multilinestring(list(matrix(11:16,3))), st_point(5:6),
st_geometrycollection(list(st_point(10:11))))
sf
objectget or set relation_to_geometry attribute of an sf
object
NA_agr_
st_agr(x, ...)
st_agr(x) < value
st_set_agr(x, value)
x 
object of class 
... 
ignored 
value 
character, or factor with appropriate levels; if named, names should correspond to the nongeometry listcolumn columns of 
An object of class factor
of length 1.
NA_agr_
is the agr
object with a missing value.
Convert sfc object to an WKB object
st_as_binary(x, ...)
## S3 method for class 'sfc'
st_as_binary(
x,
...,
EWKB = FALSE,
endian = .Platform$endian,
pureR = FALSE,
precision = attr(x, "precision"),
hex = FALSE
)
## S3 method for class 'sfg'
st_as_binary(
x,
...,
endian = .Platform$endian,
EWKB = FALSE,
pureR = FALSE,
hex = FALSE,
srid = 0
)
x 
object to convert 
... 
ignored 
EWKB 
logical; use EWKB (PostGIS), or (default) ISOWKB? 
endian 
character; either "big" or "little"; default: use that of platform 
pureR 
logical; use pure R solution, or C++? 
precision 
numeric; if zero, do not modify; to reduce precision: negative values convert to float (4byte real); positive values convert to round(x*precision)/precision. See details. 
hex 
logical; return as (unclassed) hexadecimal encoded character vector? 
srid 
integer; override srid (can be used when the srid is unavailable locally). 
st_as_binary
is called on sfc objects on their way to the GDAL or GEOS libraries, and hence does rounding (if requested) on the fly before e.g. computing spatial predicates like st_intersects. The examples show a roundtrip of an sfc
to and from binary.
For the precision model used, see also https://locationtech.github.io/jts/javadoc/org/locationtech/jts/geom/PrecisionModel.html. There, it is written that: “... to specify 3 decimal places of precision, use a scale factor of 1000. To specify 3 decimal places of precision (i.e. rounding to the nearest 1000), use a scale factor of 0.001.”. Note that ALL coordinates, so also Z or M values (if present) are affected.
# examples of setting precision:
st_point(c(1/3, 1/6)) %>% st_sfc(precision = 1000) %>% st_as_binary %>% st_as_sfc
st_point(c(1/3, 1/6)) %>% st_sfc(precision = 100) %>% st_as_binary %>% st_as_sfc
st_point(1e6 * c(1/3, 1/6)) %>% st_sfc(precision = 0.01) %>% st_as_binary %>% st_as_sfc
st_point(1e6 * c(1/3, 1/6)) %>% st_sfc(precision = 0.001) %>% st_as_binary %>% st_as_sfc
Convert sf* object to an grid graphics object (grob)
st_as_grob(x, ...)
x 
object to be converted into an object class 
... 
passed on to the xxxGrob function, e.g. 
Convert foreign object to an sf object
st_as_sf(x, ...)
## S3 method for class 'data.frame'
st_as_sf(
x,
...,
agr = NA_agr_,
coords,
wkt,
dim = "XYZ",
remove = TRUE,
na.fail = TRUE,
sf_column_name = NULL
)
## S3 method for class 'sf'
st_as_sf(x, ...)
## S3 method for class 'sfc'
st_as_sf(x, ...)
## S3 method for class 'Spatial'
st_as_sf(x, ...)
## S3 method for class 'map'
st_as_sf(x, ..., fill = TRUE, group = TRUE)
## S3 method for class 'ppp'
st_as_sf(x, ...)
## S3 method for class 'psp'
st_as_sf(x, ...)
## S3 method for class 'lpp'
st_as_sf(x, ...)
## S3 method for class 's2_geography'
st_as_sf(x, ..., crs = st_crs(4326))
x 
object to be converted into an object class 
... 
passed on to st_sf, might included named arguments 
agr 
character vector; see details section of st_sf 
coords 
in case of point data: names or numbers of the numeric columns holding coordinates 
wkt 
name or number of the character column that holds WKT encoded geometries 
dim 
passed on to st_point (only when argument coords is given) 
remove 
logical; when coords or wkt is given, remove these columns from data.frame? 
na.fail 
logical; if 
sf_column_name 
character; name of the active listcolumn with simple feature geometries; in case
there is more than one and 
fill 
logical; the value for 
group 
logical; if 
crs 
coordinate reference system to be assigned; object of class 
setting argument wkt
annihilates the use of argument coords
. If x
contains a column called "geometry", coords
will result in overwriting of this column by the sfc geometry listcolumn. Setting wkt
will replace this column with the geometry listcolumn, unless remove
is FALSE
.
pt1 = st_point(c(0,1))
pt2 = st_point(c(1,1))
st_sfc(pt1, pt2)
d = data.frame(a = 1:2)
d$geom = st_sfc(pt1, pt2)
df = st_as_sf(d)
d$geom = c("POINT(0 0)", "POINT(0 1)")
df = st_as_sf(d, wkt = "geom")
d$geom2 = st_sfc(pt1, pt2)
st_as_sf(d) # should warn
if (require(sp, quietly = TRUE)) {
data(meuse, package = "sp")
meuse_sf = st_as_sf(meuse, coords = c("x", "y"), crs = 28992, agr = "constant")
meuse_sf[1:3,]
summary(meuse_sf)
}
if (require(sp, quietly = TRUE)) {
x = rbind(c(1,1), c(1,1), c(1,1), c(1,1), c(1,1))
x1 = 0.1 * x + 0.1
x2 = 0.1 * x + 0.4
x3 = 0.1 * x + 0.7
y = x + 3
y1 = x1 + 3
y3 = x3 + 3
m = matrix(c(3, 0), 5, 2, byrow = TRUE)
z = x + m
z1 = x1 + m
z2 = x2 + m
z3 = x3 + m
p1 = Polygons(list( Polygon(x[5:1,]), Polygon(x2), Polygon(x3),
Polygon(y[5:1,]), Polygon(y1), Polygon(x1), Polygon(y3)), "ID1")
p2 = Polygons(list( Polygon(z[5:1,]), Polygon(z2), Polygon(z3), Polygon(z1)),
"ID2")
r = SpatialPolygons(list(p1,p2))
a = suppressWarnings(st_as_sf(r))
summary(a)
demo(meuse, ask = FALSE, echo = FALSE)
summary(st_as_sf(meuse))
summary(st_as_sf(meuse.grid))
summary(st_as_sf(meuse.area))
summary(st_as_sf(meuse.riv))
summary(st_as_sf(as(meuse.riv, "SpatialLines")))
pol.grd = as(meuse.grid, "SpatialPolygonsDataFrame")
# summary(st_as_sf(pol.grd))
# summary(st_as_sf(as(pol.grd, "SpatialLinesDataFrame")))
}
if (require(spatstat.geom)) {
g = st_as_sf(gorillas)
# select only the points:
g[st_is(g, "POINT"),]
}
if (require(spatstat.linnet)) {
data(chicago)
plot(st_as_sf(chicago)["label"])
plot(st_as_sf(chicago)[1,"label"])
}
Convert foreign geometry object to an sfc object
## S3 method for class 'pq_geometry'
st_as_sfc(
x,
...,
EWKB = TRUE,
spatialite = FALSE,
pureR = FALSE,
crs = NA_crs_
)
## S3 method for class 'list'
st_as_sfc(x, ..., crs = NA_crs_)
## S3 method for class 'blob'
st_as_sfc(x, ...)
## S3 method for class 'bbox'
st_as_sfc(x, ...)
## S3 method for class 'WKB'
st_as_sfc(
x,
...,
EWKB = FALSE,
spatialite = FALSE,
pureR = FALSE,
crs = NA_crs_
)
## S3 method for class 'raw'
st_as_sfc(x, ...)
## S3 method for class 'character'
st_as_sfc(x, crs = NA_integer_, ..., GeoJSON = FALSE)
## S3 method for class 'factor'
st_as_sfc(x, ...)
st_as_sfc(x, ...)
## S3 method for class 'SpatialPoints'
st_as_sfc(x, ..., precision = 0)
## S3 method for class 'SpatialPixels'
st_as_sfc(x, ..., precision = 0)
## S3 method for class 'SpatialMultiPoints'
st_as_sfc(x, ..., precision = 0)
## S3 method for class 'SpatialLines'
st_as_sfc(x, ..., precision = 0, forceMulti = FALSE)
## S3 method for class 'SpatialPolygons'
st_as_sfc(x, ..., precision = 0, forceMulti = FALSE)
## S3 method for class 'map'
st_as_sfc(x, ...)
## S3 method for class 's2_geography'
st_as_sfc(
x,
...,
crs = st_crs(4326),
endian = match(.Platform$endian, c("big", "little"))  1L
)
x 
object to convert 
... 
further arguments 
EWKB 
logical; if 
spatialite 
logical; if 
pureR 
logical; if 
crs 
coordinate reference system to be assigned; object of class 
GeoJSON 
logical; if 
precision 
precision value; see st_as_binary 
forceMulti 
logical; if 
endian 
integer; 0 or 1: defaults to the endian of the native machine 
When converting from WKB, the object x
is either a character vector such as typically obtained from PostGIS (either with leading "0x" or without), or a list with raw vectors representing the features in binary (raw) form.
If x
is a character vector, it should be a vector containing
wellknowntext, or
Postgis EWKT or GeoJSON representations of a single geometry for each vector element.
If x
is a factor
, it is converted to character
.
wkb = structure(list("01010000204071000000000000801A064100000000AC5C1441"), class = "WKB")
st_as_sfc(wkb, EWKB = TRUE)
wkb = structure(list("0x01010000204071000000000000801A064100000000AC5C1441"), class = "WKB")
st_as_sfc(wkb, EWKB = TRUE)
st_as_sfc(st_as_binary(st_sfc(st_point(0:1)))[[1]], crs = 4326)
st_as_sfc("SRID=3978;LINESTRING(1663106 105415,1664320 104617)")
Return Wellknown Text representation of simple feature geometry or coordinate reference system
## S3 method for class 'crs'
st_as_text(x, ..., projjson = FALSE, pretty = FALSE)
st_as_text(x, ...)
## S3 method for class 'sfg'
st_as_text(x, ...)
## S3 method for class 'sfc'
st_as_text(x, ..., EWKT = FALSE)
x 
object of class 
... 
modifiers; in particular 
projjson 
logical; if TRUE, return projjson form (requires GDAL 3.1 and PROJ 6.2), else return wellknowntext form 
pretty 
logical; if TRUE, print humanreadable wellknowntext representation of a coordinate reference system 
EWKT 
logical; if TRUE, print SRID=xxx; before the WKT string if 
The returned WKT representation of simple feature geometry conforms to the simple features access specification and extensions (known as EWKT, supported by PostGIS and other simple features implementations for addition of a SRID to a WKT string).
st_as_text(st_point(1:2))
st_as_text(st_sfc(st_point(c(90,40)), crs = 4326), EWKT = TRUE)
Return bounding of a simple feature or simple feature set
## S3 method for class 'bbox'
is.na(x)
st_bbox(obj, ...)
## S3 method for class 'POINT'
st_bbox(obj, ...)
## S3 method for class 'MULTIPOINT'
st_bbox(obj, ...)
## S3 method for class 'LINESTRING'
st_bbox(obj, ...)
## S3 method for class 'POLYGON'
st_bbox(obj, ...)
## S3 method for class 'MULTILINESTRING'
st_bbox(obj, ...)
## S3 method for class 'MULTIPOLYGON'
st_bbox(obj, ...)
## S3 method for class 'GEOMETRYCOLLECTION'
st_bbox(obj, ...)
## S3 method for class 'MULTISURFACE'
st_bbox(obj, ...)
## S3 method for class 'MULTICURVE'
st_bbox(obj, ...)
## S3 method for class 'CURVEPOLYGON'
st_bbox(obj, ...)
## S3 method for class 'COMPOUNDCURVE'
st_bbox(obj, ...)
## S3 method for class 'POLYHEDRALSURFACE'
st_bbox(obj, ...)
## S3 method for class 'TIN'
st_bbox(obj, ...)
## S3 method for class 'TRIANGLE'
st_bbox(obj, ...)
## S3 method for class 'CIRCULARSTRING'
st_bbox(obj, ...)
## S3 method for class 'sfc'
st_bbox(obj, ...)
## S3 method for class 'sf'
st_bbox(obj, ...)
## S3 method for class 'Spatial'
st_bbox(obj, ...)
## S3 method for class 'Raster'
st_bbox(obj, ...)
## S3 method for class 'Extent'
st_bbox(obj, ..., crs = NA_crs_)
## S3 method for class 'numeric'
st_bbox(obj, ..., crs = NA_crs_)
NA_bbox_
## S3 method for class 'bbox'
format(x, ...)
x 
object of class 
obj 
object to compute the bounding box from 
... 
for format.bbox, passed on to format to format individual numbers 
crs 
object of class 
An object of class bbox
of length 4.
NA_bbox_
represents the missing value for a bbox
object
a numeric vector of length four, with xmin
, ymin
, xmax
and ymax
values; if obj
is of class sf
, sfc
, Spatial
or Raster
, the object
returned has a class bbox
, an attribute crs
and a method to print the
bbox and an st_crs
method to retrieve the coordinate reference system
corresponding to obj
(and hence the bounding box). st_as_sfc has a
methods for bbox
objects to generate a polygon around the four bounding box points.
a = st_sf(a = 1:2, geom = st_sfc(st_point(0:1), st_point(1:2)), crs = 4326)
st_bbox(a)
st_as_sfc(st_bbox(a))
st_bbox(c(xmin = 16.1, xmax = 16.6, ymax = 48.6, ymin = 47.9), crs = st_crs(4326))
Longitudes can be broken at the antimeridian of a target central longitude
to permit plotting of (usually world) line or polygon objects centred
on the chosen central longitude. The method may only be used with
nonprojected, geographical coordinates and linestring or polygon objects.
s2 is turned off internally to permit the use of a rectangular bounding
box. If the input geometries go outside [180, 180]
degrees longitude,
the protruding geometries will also be split using the same tol=
values; in this case empty geometries will be dropped first.
st_break_antimeridian(x, lon_0 = 0, tol = 1e04, ...)
## S3 method for class 'sf'
st_break_antimeridian(x, lon_0 = 0, tol = 1e04, ...)
## S3 method for class 'sfc'
st_break_antimeridian(x, lon_0 = 0, tol = 1e04, ...)
x 
object of class 
lon_0 
target central longitude (degrees) 
tol 
half of break width (degrees, default 0.0001) 
... 
ignored here 
if (require("maps", quietly=TRUE)) {
opar = par(mfrow=c(3, 2))
wld = st_as_sf(map(fill=FALSE, interior=FALSE, plot=FALSE), fill=FALSE)
for (lon_0 in c(170, 90, 10, 10, 90, 170)) {
wld > st_break_antimeridian(lon_0=lon_0) >
st_transform(paste0("+proj=natearth +lon_0=", lon_0)) >
st_geometry() > plot(main=lon_0)
}
par(opar)
}
Cast geometry to another type: either simplify, or cast explicitly
## S3 method for class 'MULTIPOLYGON'
st_cast(x, to, ...)
## S3 method for class 'MULTILINESTRING'
st_cast(x, to, ...)
## S3 method for class 'MULTIPOINT'
st_cast(x, to, ...)
## S3 method for class 'POLYGON'
st_cast(x, to, ...)
## S3 method for class 'LINESTRING'
st_cast(x, to, ...)
## S3 method for class 'POINT'
st_cast(x, to, ...)
## S3 method for class 'GEOMETRYCOLLECTION'
st_cast(x, to, ...)
## S3 method for class 'CIRCULARSTRING'
st_cast(x, to, ...)
## S3 method for class 'MULTISURFACE'
st_cast(x, to, ...)
## S3 method for class 'COMPOUNDCURVE'
st_cast(x, to, ...)
## S3 method for class 'MULTICURVE'
st_cast(x, to, ...)
## S3 method for class 'CURVE'
st_cast(x, to, ...)
st_cast(x, to, ...)
## S3 method for class 'sfc'
st_cast(x, to, ..., ids = seq_along(x), group_or_split = TRUE)
## S3 method for class 'sf'
st_cast(x, to, ..., warn = TRUE, do_split = TRUE)
## S3 method for class 'sfc_CIRCULARSTRING'
st_cast(x, to, ...)
x 
object of class 
to 
character; target type, if missing, simplification is tried; when 
... 
ignored 
ids 
integer vector, denoting how geometries should be grouped (default: no grouping) 
group_or_split 
logical; if TRUE, group or split geometries; if FALSE, carry out a 11 pergeometry conversion. 
warn 
logical; if 
do_split 
logical; if 
When converting a GEOMETRYCOLLECTION to COMPOUNDCURVE, MULTISURFACE or CURVEPOLYGON, the user is responsible for the validity of the resulting object: no checks are being carried out by the software.
When converting mixed, GEOMETRY sets, it may help to first convert to the MULTItype, see examples
the st_cast
method for sf
objects can only split geometries, e.g. cast MULTIPOINT
into multiple POINT
features. In case of splitting, attributes are repeated and a warning is issued when nonconstant attributes are assigned to subgeometries. To merge feature geometries and attribute values, use aggregate or summarise.
object of class to
if successful, or unmodified object if unsuccessful. If information gets lost while type casting, a warning is raised.
In case to
is missing, st_cast.sfc
will coerce combinations of "POINT" and "MULTIPOINT", "LINESTRING" and "MULTILINESTRING", "POLYGON" and "MULTIPOLYGON" into their "MULTI..." form, or in case all geometries are "GEOMETRYCOLLECTION" will return a list of all the contents of the "GEOMETRYCOLLECTION" objects, or else do nothing. In case to
is specified, if to
is "GEOMETRY", geometries are not converted, else, st_cast
will try to coerce all elements into to
; ids
may be specified to group e.g. "POINT" objects into a "MULTIPOINT", if not specified no grouping takes place. If e.g. a "sfc_MULTIPOINT" is cast to a "sfc_POINT", the objects are split, so no information gets lost, unless group_or_split
is FALSE
.
# example(st_read)
nc = st_read(system.file("shape/nc.shp", package="sf"))
mpl < st_geometry(nc)[[4]]
#st_cast(x) ## error 'argument "to" is missing, with no default'
cast_all < function(xg) {
lapply(c("MULTIPOLYGON", "MULTILINESTRING", "MULTIPOINT", "POLYGON", "LINESTRING", "POINT"),
function(x) st_cast(xg, x))
}
st_sfc(cast_all(mpl))
## no closing coordinates should remain for multipoint
any(duplicated(unclass(st_cast(mpl, "MULTIPOINT")))) ## should be FALSE
## number of duplicated coordinates in the linestrings should equal the number of polygon rings
## (... in this case, won't always be true)
sum(duplicated(do.call(rbind, unclass(st_cast(mpl, "MULTILINESTRING"))))
) == sum(unlist(lapply(mpl, length))) ## should be TRUE
p1 < structure(c(0, 1, 3, 2, 1, 0, 0, 0, 2, 4, 4, 0), .Dim = c(6L, 2L))
p2 < structure(c(1, 1, 2, 1, 1, 2, 2, 1), .Dim = c(4L, 2L))
st_polygon(list(p1, p2))
mls < st_cast(st_geometry(nc)[[4]], "MULTILINESTRING")
st_sfc(cast_all(mls))
mpt < st_cast(st_geometry(nc)[[4]], "MULTIPOINT")
st_sfc(cast_all(mpt))
pl < st_cast(st_geometry(nc)[[4]], "POLYGON")
st_sfc(cast_all(pl))
ls < st_cast(st_geometry(nc)[[4]], "LINESTRING")
st_sfc(cast_all(ls))
pt < st_cast(st_geometry(nc)[[4]], "POINT")
## st_sfc(cast_all(pt)) ## Error: cannot create MULTIPOLYGON from POINT
st_sfc(lapply(c("POINT", "MULTIPOINT"), function(x) st_cast(pt, x)))
s = st_multipoint(rbind(c(1,0)))
st_cast(s, "POINT")
# https://github.com/rspatial/sf/issues/1930:
pt1 < st_point(c(0,1))
pt23 < st_multipoint(matrix(c(1,2,3,4), ncol = 2, byrow = TRUE))
d < st_sf(geom = st_sfc(pt1, pt23))
st_cast(d, "POINT") # will not convert the entire MULTIPOINT, and warns
st_cast(d, "MULTIPOINT") %>% st_cast("POINT")
Mixes of POINTS and MULTIPOINTS, LINESTRING and MULTILINESTRING, POLYGON and MULTIPOLYGON are returned as MULTIPOINTS, MULTILINESTRING and MULTIPOLYGONS respectively
st_cast_sfc_default(x)
x 
list of geometries or simple features 
Geometries that are already MULTI* are left unchanged. Features that can't be cast to a single MULTI* geometry are return as a GEOMETRYCOLLECTION
GEOMETRY
or GEOMETRYCOLLECTION
,
return an object consisting only of elements of the specified type.Similar to ST_CollectionExtract in PostGIS. If there are no subgeometries of the specified type, an empty geometry is returned.
st_collection_extract(
x,
type = c("POLYGON", "POINT", "LINESTRING"),
warn = FALSE
)
## S3 method for class 'sfg'
st_collection_extract(
x,
type = c("POLYGON", "POINT", "LINESTRING"),
warn = FALSE
)
## S3 method for class 'sfc'
st_collection_extract(
x,
type = c("POLYGON", "POINT", "LINESTRING"),
warn = FALSE
)
## S3 method for class 'sf'
st_collection_extract(
x,
type = c("POLYGON", "POINT", "LINESTRING"),
warn = FALSE
)
x 
an object of class 
type 
character; one of "POLYGON", "POINT", "LINESTRING" 
warn 
logical; if 
An object having the same class as x
, with geometries
consisting only of elements of the specified type.
For sfg
objects, an sfg
object is returned if there is only
one geometry of the specified type, otherwise the geometries are combined
into an sfc
object of the relevant type. If any subgeometries in the
input are MULTI, then all of the subgeometries in the output will be MULTI.
pt < st_point(c(1, 0))
ls < st_linestring(matrix(c(4, 3, 0, 0), ncol = 2))
poly1 < st_polygon(list(matrix(c(5.5, 7, 7, 6, 5.5, 0, 0, 0.5, 0.5, 0), ncol = 2)))
poly2 < st_polygon(list(matrix(c(6.6, 8, 8, 7, 6.6, 1, 1, 1.5, 1.5, 1), ncol = 2)))
multipoly < st_multipolygon(list(poly1, poly2))
i < st_geometrycollection(list(pt, ls, poly1, poly2))
j < st_geometrycollection(list(pt, ls, poly1, poly2, multipoly))
st_collection_extract(i, "POLYGON")
st_collection_extract(i, "POINT")
st_collection_extract(i, "LINESTRING")
## A GEOMETRYCOLLECTION
aa < rbind(st_sf(a=1, geom = st_sfc(i)),
st_sf(a=2, geom = st_sfc(j)))
## With sf objects
st_collection_extract(aa, "POLYGON")
st_collection_extract(aa, "LINESTRING")
st_collection_extract(aa, "POINT")
## With sfc objects
st_collection_extract(st_geometry(aa), "POLYGON")
st_collection_extract(st_geometry(aa), "LINESTRING")
st_collection_extract(st_geometry(aa), "POINT")
## A GEOMETRY of single types
bb < rbind(
st_sf(a = 1, geom = st_sfc(pt)),
st_sf(a = 2, geom = st_sfc(ls)),
st_sf(a = 3, geom = st_sfc(poly1)),
st_sf(a = 4, geom = st_sfc(multipoly))
)
st_collection_extract(bb, "POLYGON")
## A GEOMETRY of mixed single types and GEOMETRYCOLLECTIONS
cc < rbind(aa, bb)
st_collection_extract(cc, "POLYGON")
retrieve coordinates in matrix form
st_coordinates(x, ...)
x 
object of class sf, sfc or sfg 
... 
ignored 
matrix with coordinates (X, Y, possibly Z and/or M) in rows, possibly followed by integer indicators L1
,...,L3
that point out to which structure the coordinate belongs; for POINT
this is absent (each coordinate is a feature), for LINESTRING
L1
refers to the feature, for MULTILINESTRING
L1
refers to the part and L2
to the simple feature, for POLYGON
L1
refers to the main ring or holes and L2
to the simple feature, for MULTIPOLYGON
L1
refers to the main ring or holes, L2
to the ring id in the MULTIPOLYGON
, and L3
to the simple feature.
For POLYGONS
, L1
can be used to identify exterior rings and inner holes.
The exterior ring is when L1
is equal to 1. Interior rings are identified
when L1
is greater than 1. L2
can be used to differentiate between the
feature. Whereas for MULTIPOLYGON
, L3
refers to the MULTIPOLYGON
feature and L2
refers to the component POLYGON
.
crop an sf object to a specific rectangle
st_crop(x, y, ...)
## S3 method for class 'sfc'
st_crop(x, y, ..., xmin, ymin, xmax, ymax)
## S3 method for class 'sf'
st_crop(x, y, ...)
x 
object of class 
y 
numeric vector with named elements 
... 
ignored 
xmin 
minimum x extent of cropping area 
ymin 
minimum y extent of cropping area 
xmax 
maximum x extent of cropping area 
ymax 
maximum y extent of cropping area 
setting arguments xmin
, ymin
, xmax
and ymax
implies that argument y
gets ignored.
box = c(xmin = 0, ymin = 0, xmax = 1, ymax = 1)
pol = st_sfc(st_buffer(st_point(c(.5, .5)), .6))
pol_sf = st_sf(a=1, geom=pol)
plot(st_crop(pol, box))
plot(st_crop(pol_sf, st_bbox(box)))
# alternative:
plot(st_crop(pol, xmin = 0, ymin = 0, xmax = 1, ymax = 1))
Retrieve coordinate reference system from sf or sfc object
Set or replace retrieve coordinate reference system from object
st_crs(x, ...)
## S3 method for class 'sf'
st_crs(x, ...)
## S3 method for class 'numeric'
st_crs(x, ...)
## S3 method for class 'character'
st_crs(x, ...)
## S3 method for class 'sfc'
st_crs(x, ..., parameters = FALSE)
## S3 method for class 'bbox'
st_crs(x, ...)
## S3 method for class 'CRS'
st_crs(x, ...)
## S3 method for class 'crs'
st_crs(x, ...)
st_crs(x) < value
## S3 replacement method for class 'sf'
st_crs(x) < value
## S3 replacement method for class 'sfc'
st_crs(x) < value
st_set_crs(x, value)
NA_crs_
## S3 method for class 'crs'
is.na(x)
## S3 method for class 'crs'
x$name
## S3 method for class 'crs'
format(x, ...)
st_axis_order(authority_compliant = logical(0))
x 

... 
ignored 
parameters 
logical; 
value 
one of (i) character: a string accepted by GDAL, (ii) integer, a valid EPSG value (numeric), or (iii) an object of class 
name 
element name 
authority_compliant 
logical; specify whether axis order should be handled compliant to the authority; if omitted, the current value is printed. 
An object of class crs
of length 2.
The *crs functions create, get, set or replace the crs
attribute
of a simple feature geometry listcolumn. This attribute is of class crs
,
and is a list consisting of input
(user input, e.g. "EPSG:4326" or "WGS84"
or a proj4string), and wkt
, an automatically generated wkt2 representation of the crs.
If x
is identical to the wkt2 representation, and the CRS has a name, this name
is used for the input
field.
Comparison of two objects of class crs
uses the GDAL function
OGRSpatialReference::IsSame
.
In case a coordinate reference system is replaced, no transformation takes place and a warning is raised to stress this.
NA_crs_
is the crs
object with missing values for input
and wkt
.
the $
method for crs
objects retrieves named elements
using the GDAL interface; named elements include
SemiMajor
, SemiMinor
, InvFlattening
, IsGeographic
,
units_gdal
, IsVertical
, WktPretty
, Wkt
,
Name
, proj4string
, epsg
, yx
,
ud_unit
, and axes
(this may be subject to changes in future GDAL versions).
Note that not all valid CRS have a corresponding proj4string
.
ud_unit
returns a valid units object or NULL
if units are missing.
format.crs returns NA if the crs is missing valued, or else the name of a crs if it is different from "unknown", or else the user input if it was set, or else its "proj4string" representation;
st_axis_order
can be used to get and set the axis order: TRUE
indicates axes order according to the authority
(e.g. EPSG:4326 defining coordinates to be latitude,longitude pairs), FALSE
indicates the usual GIS (display) order (longitude,latitude). This can be useful
when data are read, or have to be written, with coordinates in authority compliant order.
The return value is the current state of this (FALSE
, by default).
If x
is numeric, return crs
object for EPSG:x
;
if x
is character, return crs
object for x
;
if x
is of class sf
or sfc
, return its crs
object.
Object of class crs
, which is a list with elements input
(length1 character)
and wkt
(length1 character).
Elements may be NA
valued; if all elements are NA
the CRS is missing valued, and coordinates are
assumed to relate to an arbitrary Cartesian coordinate system.
st_axis_order
returns the (logical) current value if called without
argument, or (invisibly) the previous value if it is being set.
sfc = st_sfc(st_point(c(0,0)), st_point(c(1,1)))
sf = st_sf(a = 1:2, geom = sfc)
st_crs(sf) = 4326
st_geometry(sf)
sfc = st_sfc(st_point(c(0,0)), st_point(c(1,1)))
st_crs(sfc) = 4326
sfc
sfc = st_sfc(st_point(c(0,0)), st_point(c(1,1)))
sfc %>% st_set_crs(4326) %>% st_transform(3857)
st_crs("EPSG:3857")$input
st_crs(3857)$proj4string
pt = st_sfc(st_point(c(0, 60)), crs = 4326)
# st_axis_order() only has effect in GDAL >= 2.5.0:
st_axis_order() # query default: FALSE means interpret pt as (longitude latitude)
st_transform(pt, 3857)[[1]]
old_value = FALSE
if (sf_extSoftVersion()["GDAL"] >= "2.5.0")
(old_value = st_axis_order(TRUE))
# now interpret pt as (latitude longitude), as EPSG:4326 prescribes:
st_axis_order() # query current value
st_transform(pt, 3857)[[1]]
st_axis_order(old_value) # set back to old value
Get a list of the available GDAL drivers
st_drivers(what = "vector", regex)
what 
character: 
regex 
character; regular expression to filter the 
The drivers available will depend on the installation of GDAL/OGR,
and can vary; the st_drivers()
function shows all the drivers that are
readable, and which may be written. The field vsi
refers to the driver's
capability to read/create datasets through the VSI*L API. See GDAL website for additional details on driver support.
A data.frame
with driver metadata.
# The following driver lists depend on the GDAL setup and platform used:
st_drivers()
st_drivers("raster", "GeoT")
Get, set, replace or rename geometry from an sf object
## S3 method for class 'sfc'
st_geometry(obj, ...)
st_geometry(obj, ...)
## S3 method for class 'sf'
st_geometry(obj, ...)
## S3 method for class 'sfc'
st_geometry(obj, ...)
## S3 method for class 'sfg'
st_geometry(obj, ...)
st_geometry(x) < value
st_set_geometry(x, value)
st_drop_geometry(x, ...)
## S3 method for class 'sf'
st_drop_geometry(x, ...)
## Default S3 method:
st_drop_geometry(x, ...)
obj 
object of class 
... 
ignored 
x 
object of class 
value 
object of class 
when applied to a data.frame
and when value
is an object of class sfc
, st_set_geometry
and st_geometry<
will first check for the existence of an attribute sf_column
and overwrite that, or else look for listcolumns of class sfc
and overwrite the first of that, or else write the geometry listcolumn to a column named geometry
. In case value
is character and x
is of class sf
, the "active" geometry column is set to x[[value]]
.
the replacement function applied to sf
objects will overwrite the geometry listcolumn, if value
is NULL
, it will remove it and coerce x
to a data.frame
.
if x
is of class sf
, st_drop_geometry
drops the geometry of its argument, and reclasses it accordingly; otherwise it returns x
unmodified.
st_geometry returns an object of class sfc, a listcolumn with geometries
st_geometry
returns an object of class sfc. Assigning geometry to a data.frame
creates an sf object, assigning it to an sf object replaces the geometry listcolumn.
df = data.frame(a = 1:2)
sfc = st_sfc(st_point(c(3,4)), st_point(c(10,11)))
st_geometry(sfc)
st_geometry(df) < sfc
class(df)
st_geometry(df)
st_geometry(df) < sfc # replaces
st_geometry(df) < NULL # remove geometry, coerce to data.frame
sf < st_set_geometry(df, sfc) # set geometry, return sf
st_set_geometry(sf, NULL) # remove geometry, coerce to data.frame
Return geometry type of an object, as a factor
st_geometry_type(x, by_geometry = TRUE)
x 

by_geometry 
logical; if 
a factor with the geometry type of each simple feature geometry
in x
, or that of the whole set
Compute graticules and their parameters
st_graticule(
x = c(180, 90, 180, 90),
crs = st_crs(x),
datum = st_crs(4326),
...,
lon = NULL,
lat = NULL,
ndiscr = 100,
margin = 0.001
)
x 
object of class 
crs 
object of class 
datum 
either an object of class 
... 
ignored 
lon 
numeric; values in degrees East for the meridians, associated with 
lat 
numeric; values in degrees North for the parallels, associated with 
ndiscr 
integer; number of points to discretize a parallel or meridian 
margin 
numeric; small number to trim a longlat bounding box that touches or crosses +/180 long or +/90 latitude. 
an object of class sf
with additional attributes describing the type
(E: meridian, N: parallel) degree value, label, start and end coordinates and angle;
see example.
In cartographic visualization, the use of graticules is not advised, unless the graphical output will be used for measurement or navigation, or the direction of North is important for the interpretation of the content, or the content is intended to display distortions and artifacts created by projection. Unnecessary use of graticules only adds visual clutter but little relevant information. Use of coastlines, administrative boundaries or place names permits most viewers of the output to orient themselves better than a graticule.
library(sf)
if (require(maps, quietly = TRUE)) {
usa = st_as_sf(map('usa', plot = FALSE, fill = TRUE))
laea = st_crs("+proj=laea +lat_0=30 +lon_0=95") # Lambert equal area
usa < st_transform(usa, laea)
bb = st_bbox(usa)
bbox = st_linestring(rbind(c( bb[1],bb[2]),c( bb[3],bb[2]),
c( bb[3],bb[4]),c( bb[1],bb[4]),c( bb[1],bb[2])))
g = st_graticule(usa)
plot(usa, xlim = 1.2 * c(2450853.4, 2186391.9), reset = FALSE)
plot(g[1], add = TRUE, col = 'grey')
plot(bbox, add = TRUE)
points(g$x_start, g$y_start, col = 'red')
points(g$x_end, g$y_end, col = 'blue')
invisible(lapply(seq_len(nrow(g)), function(i) {
if (g$type[i] == "N" && g$x_start[i]  min(g$x_start) < 1000)
text(g[i,"x_start"], g[i,"y_start"], labels = parse(text = g[i,"degree_label"]),
srt = g$angle_start[i], pos = 2, cex = .7)
if (g$type[i] == "E" && g$y_start[i]  min(g$y_start) < 1000)
text(g[i,"x_start"], g[i,"y_start"], labels = parse(text = g[i,"degree_label"]),
srt = g$angle_start[i]  90, pos = 1, cex = .7)
if (g$type[i] == "N" && g$x_end[i]  max(g$x_end) > 1000)
text(g[i,"x_end"], g[i,"y_end"], labels = parse(text = g[i,"degree_label"]),
srt = g$angle_end[i], pos = 4, cex = .7)
if (g$type[i] == "E" && g$y_end[i]  max(g$y_end) > 1000)
text(g[i,"x_end"], g[i,"y_end"], labels = parse(text = g[i,"degree_label"]),
srt = g$angle_end[i]  90, pos = 3, cex = .7)
}))
plot(usa, graticule = st_crs(4326), axes = TRUE, lon = seq(60,130,by=10))
}
test equality between the geometry type and a class or set of classes
st_is(x, type)
x 
object of class 
type 
character; class, or set of classes, to test against 
st_is(st_point(0:1), "POINT")
sfc = st_sfc(st_point(0:1), st_linestring(matrix(1:6,,2)))
st_is(sfc, "POINT")
st_is(sfc, "POLYGON")
st_is(sfc, "LINESTRING")
st_is(st_sf(a = 1:2, sfc), "LINESTRING")
st_is(sfc, c("POINT", "LINESTRING"))
Assert whether simple feature coordinates are longlat degrees
st_is_longlat(x)
x 
object of class sf or sfc, or otherwise an object of a class that has an st_crs method returning a 
TRUE
if x
has geographic coordinates, FALSE
if it has projected coordinates, or NA
if is.na(st_crs(x))
.
jitter geometries
st_jitter(x, amount, factor = 0.002)
x 
object of class 
amount 
numeric; amount of jittering applied; if missing, the amount is set to factor * the bounding box diagonal; units of coordinates. 
factor 
numeric; fractional amount of jittering to be applied 
jitters coordinates with an amount such that runif(1, amount, amount)
is added to the coordinates. x and ycoordinates are jittered independently but all coordinates of a single geometry are jittered with the same amount, meaning that the geometry shape does not change. For longlat data, a latitude correction is made such that jittering in East and North directions are identical in distance in the center of the bounding box of x
.
nc = st_read(system.file("gpkg/nc.gpkg", package="sf"))
pts = st_centroid(st_geometry(nc))
plot(pts)
plot(st_jitter(pts, .05), add = TRUE, col = 'red')
plot(st_geometry(nc))
plot(st_jitter(st_geometry(nc), factor = .01), add = TRUE, col = '#ff8888')
spatial join, spatial filter
st_join(x, y, join, ...)
## S3 method for class 'sf'
st_join(
x,
y,
join = st_intersects,
...,
suffix = c(".x", ".y"),
left = TRUE,
largest = FALSE
)
st_filter(x, y, ...)
## S3 method for class 'sf'
st_filter(x, y, ..., .predicate = st_intersects)
x 
object of class 
y 
object of class 
join 
geometry predicate function with the same profile as st_intersects; see details 
... 
for 
suffix 
length 2 character vector; see merge 
left 
logical; if 
largest 
logical; if 
.predicate 
geometry predicate function with the same profile as st_intersects; see details 
alternative values for argument join
are:
any userdefined function of the same profile as the above
A left join returns all records of the x
object with y
fields for nonmatched records filled with NA
values; an inner join returns only records that spatially match.
To replicate the results of st_within(x, y)
you will need to use st_join(x, y, join = "st_within", left = FALSE)
.
an object of class sf
, joined based on geometry
a = st_sf(a = 1:3,
geom = st_sfc(st_point(c(1,1)), st_point(c(2,2)), st_point(c(3,3))))
b = st_sf(a = 11:14,
geom = st_sfc(st_point(c(10,10)), st_point(c(2,2)), st_point(c(2,2)), st_point(c(3,3))))
st_join(a, b)
st_join(a, b, left = FALSE)
# two ways to aggregate y's attribute values outcome over x's geometries:
st_join(a, b) %>% aggregate(list(.$a.x), mean)
if (require(dplyr, quietly = TRUE)) {
st_join(a, b) %>% group_by(a.x) %>% summarise(mean(a.y))
}
# example of largest = TRUE:
nc < st_transform(st_read(system.file("shape/nc.shp", package="sf")), 2264)
gr = st_sf(
label = apply(expand.grid(1:10, LETTERS[10:1])[,2:1], 1, paste0, collapse = " "),
geom = st_make_grid(st_as_sfc(st_bbox(nc))))
gr$col = sf.colors(10, categorical = TRUE, alpha = .3)
# cut, to check, NA's work out:
gr = gr[(1:30),]
nc_j < st_join(nc, gr, largest = TRUE)
# the two datasets:
opar = par(mfrow = c(2,1), mar = rep(0,4))
plot(st_geometry(nc_j))
plot(st_geometry(gr), add = TRUE, col = gr$col)
text(st_coordinates(st_centroid(gr)), labels = gr$label)
# the joined dataset:
plot(st_geometry(nc_j), border = 'black', col = nc_j$col)
text(st_coordinates(st_centroid(nc_j)), labels = nc_j$label, cex = .8)
plot(st_geometry(gr), border = 'green', add = TRUE)
par(opar)
# st_filter keeps the geometries in x where .predicate(x,y) returns any match in y for x
st_filter(a, b)
# for an antijoin, use the union of y
st_filter(a, st_union(b), .predicate = st_disjoint)
Return properties of layers in a datasource
st_layers(dsn, options = character(0), do_count = FALSE)
dsn 
data source name (interpretation varies by driver  for some drivers, 
options 
character; driver dependent dataset open options, multiple options supported. 
do_count 
logical; if TRUE, count the features by reading them, even if their count is not reported by the driver 
list object of class sf_layers
with elements
name of the layer
list with for each layer the geometry types
number of features (if reported; see do_count
)
number of fields
list with for each layer the crs
object
Project point on linestring, interpolate along a linestring
st_line_project(line, point, normalized = FALSE)
st_line_interpolate(line, dist, normalized = FALSE)
line 
object of class 
point 
object of class 
normalized 
logical; if 
dist 
numeric, vector with distance value(s) 
arguments line
, point
and dist
are recycled to common length when needed
st_line_project
returns the distance(s) of point(s) along line(s), when projected on the line(s)
st_line_interpolate
returns the point(s) at dist(s), when measured along (interpolated on) the line(s)
st_line_project(st_as_sfc("LINESTRING (0 0, 10 10)"), st_as_sfc(c("POINT (0 0)", "POINT (5 5)")))
st_line_project(st_as_sfc("LINESTRING (0 0, 10 10)"), st_as_sfc("POINT (5 5)"), TRUE)
st_line_interpolate(st_as_sfc("LINESTRING (0 0, 1 1)"), 1)
st_line_interpolate(st_as_sfc("LINESTRING (0 0, 1 1)"), 1, TRUE)
Sample points on a linear geometry
st_line_sample(x, n, density, type = "regular", sample = NULL)
x 
object of class 
n 
integer; number of points to choose per geometry; if missing, n will be computed as 
density 
numeric; density (points per distance unit) of the sampling, possibly a vector of length equal to the number of features (otherwise recycled); 
type 
character; indicate the sampling type, either "regular" or "random" 
sample 
numeric; a vector of numbers between 0 and 1 indicating the points to sample  if defined sample overrules n, density and type. 
ls = st_sfc(st_linestring(rbind(c(0,0),c(0,1))),
st_linestring(rbind(c(0,0),c(10,0))))
st_line_sample(ls, density = 1)
ls = st_sfc(st_linestring(rbind(c(0,0),c(0,1))),
st_linestring(rbind(c(0,0),c(.1,0))), crs = 4326)
try(st_line_sample(ls, density = 1/1000)) # error
st_line_sample(st_transform(ls, 3857), n = 5) # five points for each line
st_line_sample(st_transform(ls, 3857), n = c(1, 3)) # one and three points
st_line_sample(st_transform(ls, 3857), density = 1/1000) # one per km
st_line_sample(st_transform(ls, 3857), density = c(1/1000, 1/10000)) # one per km, one per 10 km
st_line_sample(st_transform(ls, 3857), density = units::set_units(1, 1/km)) # one per km
# five equidistant points including start and end:
st_line_sample(st_transform(ls, 3857), sample = c(0, 0.25, 0.5, 0.75, 1))
Return 'm' range of a simple feature or simple feature set
## S3 method for class 'm_range'
is.na(x)
st_m_range(obj, ...)
## S3 method for class 'POINT'
st_m_range(obj, ...)
## S3 method for class 'MULTIPOINT'
st_m_range(obj, ...)
## S3 method for class 'LINESTRING'
st_m_range(obj, ...)
## S3 method for class 'POLYGON'
st_m_range(obj, ...)
## S3 method for class 'MULTILINESTRING'
st_m_range(obj, ...)
## S3 method for class 'MULTIPOLYGON'
st_m_range(obj, ...)
## S3 method for class 'GEOMETRYCOLLECTION'
st_m_range(obj, ...)
## S3 method for class 'MULTISURFACE'
st_m_range(obj, ...)
## S3 method for class 'MULTICURVE'
st_m_range(obj, ...)
## S3 method for class 'CURVEPOLYGON'
st_m_range(obj, ...)
## S3 method for class 'COMPOUNDCURVE'
st_m_range(obj, ...)
## S3 method for class 'POLYHEDRALSURFACE'
st_m_range(obj, ...)
## S3 method for class 'TIN'
st_m_range(obj, ...)
## S3 method for class 'TRIANGLE'
st_m_range(obj, ...)
## S3 method for class 'CIRCULARSTRING'
st_m_range(obj, ...)
## S3 method for class 'sfc'
st_m_range(obj, ...)
## S3 method for class 'sf'
st_m_range(obj, ...)
## S3 method for class 'numeric'
st_m_range(obj, ..., crs = NA_crs_)
NA_m_range_
x 
object of class 
obj 
object to compute the m range from 
... 
ignored 
crs 
object of class 
An object of class m_range
of length 2.
NA_m_range_
represents the missing value for a m_range
object
a numeric vector of length two, with mmin
and mmax
values;
if obj
is of class sf
or sfc
the object
if obj
is of class sf
or sfc
the object
returned has a class m_range
a = st_sf(a = 1:2, geom = st_sfc(st_point(0:3), st_point(1:4)), crs = 4326)
st_m_range(a)
st_m_range(c(mmin = 16.1, mmax = 16.6), crs = st_crs(4326))
Create a square or hexagonal grid covering the bounding box of the geometry of an sf or sfc object
st_make_grid(
x,
cellsize = c(diff(st_bbox(x)[c(1, 3)]), diff(st_bbox(x)[c(2, 4)]))/n,
offset = st_bbox(x)[c("xmin", "ymin")],
n = c(10, 10),
crs = if (missing(x)) NA_crs_ else st_crs(x),
what = "polygons",
square = TRUE,
flat_topped = FALSE
)
x 

cellsize 
numeric of length 1 or 2 with target cellsize: for square or rectangular cells the width and height, for hexagonal cells the distance between opposite edges (edge length is cellsize/sqrt(3)). A length units object can be passed, or an area unit object with area size of the square or hexagonal cell. 
offset 
numeric of length 2; lower left corner coordinates (x, y) of the grid 
n 
integer of length 1 or 2, number of grid cells in x and y direction (columns, rows) 
crs 
object of class 
what 
character; one of: 
square 
logical; if 
flat_topped 
logical; if 
Object of class sfc
(simple feature geometry list column) with, depending on what
and square
,
square or hexagonal polygons, corner points of these polygons, or center points of these polygons.
plot(st_make_grid(what = "centers"), axes = TRUE)
plot(st_make_grid(what = "corners"), add = TRUE, col = 'green', pch=3)
sfc = st_sfc(st_polygon(list(rbind(c(0,0), c(1,0), c(1,1), c(0,0)))))
plot(st_make_grid(sfc, cellsize = .1, square = FALSE))
plot(sfc, add = TRUE)
# nondefault offset:
plot(st_make_grid(sfc, cellsize = .1, square = FALSE, offset = c(0, .05 / (sqrt(3)/2))))
plot(sfc, add = TRUE)
nc = st_read(system.file("shape/nc.shp", package="sf"))
g = st_make_grid(nc)
plot(g)
plot(st_geometry(nc), add = TRUE)
# g[nc] selects cells that intersect with nc:
plot(g[nc], col = '#ff000088', add = TRUE)
get index of nearest feature
st_nearest_feature(
x,
y,
...,
check_crs = TRUE,
longlat = isTRUE(st_is_longlat(x))
)
x 
object of class 
y 
object of class 
... 
ignored 
check_crs 
logical; should 
longlat 
logical; does 
for each feature (geometry) in x
the index of the nearest feature (geometry) in
set y
, or in the remaining set of x
if y
is missing;
empty geometries result in NA
indexes
st_nearest_points for finding the nearest points for pairs of feature geometries
ls1 = st_linestring(rbind(c(0,0), c(1,0)))
ls2 = st_linestring(rbind(c(0,0.1), c(1,0.1)))
ls3 = st_linestring(rbind(c(0,1), c(1,1)))
(l = st_sfc(ls1, ls2, ls3))
p1 = st_point(c(0.1, 0.1))
p2 = st_point(c(0.1, 0.11))
p3 = st_point(c(0.1, 0.09))
p4 = st_point(c(0.1, 0.9))
(p = st_sfc(p1, p2, p3, p4))
try(st_nearest_feature(p, l))
try(st_nearest_points(p, l[st_nearest_feature(p,l)], pairwise = TRUE))
r = sqrt(2)/10
b1 = st_buffer(st_point(c(.1,.1)), r)
b2 = st_buffer(st_point(c(.9,.9)), r)
b3 = st_buffer(st_point(c(.9,.1)), r)
circles = st_sfc(b1, b2, b3)
plot(circles, col = NA, border = 2:4)
pts = st_sfc(st_point(c(.3,.1)), st_point(c(.6,.2)), st_point(c(.6,.6)), st_point(c(.4,.8)))
plot(pts, add = TRUE, col = 1)
# draw points to nearest circle:
nearest = try(st_nearest_feature(pts, circles))
if (inherits(nearest, "tryerror")) # GEOS 3.6.1 not available
nearest = c(1, 3, 2, 2)
ls = st_nearest_points(pts, circles[nearest], pairwise = TRUE)
plot(ls, col = 5:8, add = TRUE)
# compute distance between pairs of nearest features:
st_distance(pts, circles[nearest], by_element = TRUE)
get nearest points between pairs of geometries
st_nearest_points(x, y, ...)
## S3 method for class 'sfc'
st_nearest_points(x, y, ..., pairwise = FALSE)
## S3 method for class 'sfg'
st_nearest_points(x, y, ...)
## S3 method for class 'sf'
st_nearest_points(x, y, ...)
x 
object of class 
y 
object of class 
... 
ignored 
pairwise 
logical; if 
in case x
lies inside y
, when using S2, the end points
are on polygon boundaries, when using GEOS the end point are identical to x
.
an sfc object with all twopoint LINESTRING
geometries of point pairs from the first to the second geometry, of length x * y, with y cycling fastest. See examples for ideas how to convert these to POINT
geometries.
st_nearest_feature for finding the nearest feature
r = sqrt(2)/10
pt1 = st_point(c(.1,.1))
pt2 = st_point(c(.9,.9))
pt3 = st_point(c(.9,.1))
b1 = st_buffer(pt1, r)
b2 = st_buffer(pt2, r)
b3 = st_buffer(pt3, r)
(ls0 = st_nearest_points(b1, b2)) # sfg
(ls = st_nearest_points(st_sfc(b1), st_sfc(b2, b3))) # sfc
plot(b1, xlim = c(.2,1.2), ylim = c(.2,1.2), col = NA, border = 'green')
plot(st_sfc(b2, b3), add = TRUE, col = NA, border = 'blue')
plot(ls, add = TRUE, col = 'red')
nc = st_read(system.file("gpkg/nc.gpkg", package="sf"))
plot(st_geometry(nc))
ls = st_nearest_points(nc[1,], nc)
plot(ls, col = 'red', add = TRUE)
pts = st_cast(ls, "POINT") # gives all start & end points
# starting, "from" points, corresponding to x:
plot(pts[seq(1, 200, 2)], add = TRUE, col = 'blue')
# ending, "to" points, corresponding to y:
plot(pts[seq(2, 200, 2)], add = TRUE, col = 'green')
st_normalize
transforms the coordinates in the input feature to fall
between 0 and 1. By default the current domain is set to the bounding box of
the input, but other domains can be used as well
st_normalize(x, domain = st_bbox(x), ...)
x 
object of class sf, sfc or sfg 
domain 
The domain 
... 
ignored 
p1 = st_point(c(7,52))
st_normalize(p1, domain = c(0, 0, 10, 100))
p2 = st_point(c(30,20))
sfc = st_sfc(p1, p2, crs = 4326)
sfc
sfc_norm < st_normalize(sfc)
st_bbox(sfc_norm)
Get precision
Set precision
st_precision(x)
st_set_precision(x, precision)
st_precision(x) < value
x 
object of class 
precision 
numeric, or object of class 
value 
precision value 
If precision
is a units
object, the object on which we set precision must have a coordinate reference system with compatible distance units.
Setting a precision
has no direct effect on coordinates of geometries, but merely set an attribute tag to an sfc
object.
The effect takes place in st_as_binary or, more precise, in the C++ function CPL_write_wkb
, where simple feature geometries are being serialized to wellknownbinary (WKB).
This happens always when routines are called in GEOS library (geometrical operations or predicates), for writing geometries using st_write or write_sf, st_make_valid
in package lwgeom
; also aggregate and summarise by default union geometries, which calls a GEOS library function.
Routines in these libraries receive rounded coordinates, and possibly return results based on them. st_as_binary contains an example of a roundtrip of sfc
geometries through WKB, in order to see the rounding happening to R data.
The reason to support precision is that geometrical operations in GEOS or liblwgeom may work better at reduced precision. For writing data from R to external resources it is harder to think of a good reason to limiting precision.
st_as_binary for an explanation of what setting precision does, and the examples therein.
x < st_sfc(st_point(c(pi, pi)))
st_precision(x)
st_precision(x) < 0.01
st_precision(x)
Read simple features from file or database, or retrieve layer names and their geometry type(s)
Read PostGIS table directly through DBI and RPostgreSQL interface, converting WellKnow Binary geometries to sfc
st_read(dsn, layer, ...)
## S3 method for class 'character'
st_read(
dsn,
layer,
...,
query = NA,
options = NULL,
quiet = FALSE,
geometry_column = 1L,
type = 0,
promote_to_multi = TRUE,
stringsAsFactors = sf_stringsAsFactors(),
int64_as_string = FALSE,
check_ring_dir = FALSE,
fid_column_name = character(0),
drivers = character(0),
wkt_filter = character(0),
optional = FALSE,
use_stream = default_st_read_use_stream()
)
read_sf(..., quiet = TRUE, stringsAsFactors = FALSE, as_tibble = TRUE)
## S3 method for class 'DBIObject'
st_read(
dsn = NULL,
layer = NULL,
query = NULL,
EWKB = TRUE,
quiet = TRUE,
as_tibble = FALSE,
geometry_column = NULL,
...
)
dsn 
data source name (interpretation varies by driver  for some
drivers, 
layer 
layer name (varies by driver, may be a file name without
extension); in case 
... 
parameter(s) passed on to st_as_sf 
query 
SQL query to select records; see details 
options 
character; driver dependent dataset open options, multiple options supported. For possible values, see the "Open options" section of the GDAL documentation of the corresponding driver, and https://github.com/rspatial/sf/issues/1157 for an example. 
quiet 
logical; suppress info on name, driver, size and spatial reference, or signaling no or multiple layers 
geometry_column 
integer or character; in case of multiple geometry fields, which one to take? 
type 
integer; ISO number of desired simple feature type; see details.
If left zero, and 
promote_to_multi 
logical; in case of a mix of Point and MultiPoint, or
of LineString and MultiLineString, or of Polygon and MultiPolygon, convert
all to the Multi variety; defaults to 
stringsAsFactors 
logical; logical: should character vectors be
converted to factors? Default for 
int64_as_string 
logical; if 
check_ring_dir 
logical; if 
fid_column_name 
character; name of column to write feature IDs to; defaults to not doing this 
drivers 
character; limited set of driver short names to be tried (default: try all) 
wkt_filter 
character; WKT representation of a spatial filter (may be used as bounding box, selecting overlapping geometries); see examples 
optional 
logical; passed to as.data.frame; always 
use_stream 
Use 
as_tibble 
logical; should the returned table be of class tibble or data.frame? 
EWKB 
logical; is the WKB of type EWKB? if missing, defaults to

for geometry_column
, see also
https://trac.osgeo.org/gdal/wiki/rfc41_multiple_geometry_fields
for values for type
see
https://en.wikipedia.org/wiki/Wellknown_text#Wellknown_binary, but
note that not every target value may lead to successful conversion. The
typical conversion from POLYGON (3) to MULTIPOLYGON (6) should work; the
other way around (type=3), secondary rings from MULTIPOLYGONS may be dropped
without warnings. promote_to_multi
is handled on a pergeometry column
basis; type
may be specified for each geometry column.
Note that stray files in data source directories (such as *.dbf
) may
lead to spurious errors that accompanying *.shp
are missing.
In case of problems reading shapefiles from USB drives on OSX, please see
https://github.com/rspatial/sf/issues/252. Reading shapefiles (or other
data sources) directly from zip files can be done by prepending the path
with /vsizip/
. This is part of the GDAL Virtual File Systems interface
that also supports .gz, curl, and other operations, including chaining; see
https://gdal.org/user/virtual_file_systems.html for a complete
description and examples.
For query
with a character dsn
the query text is handed to
'ExecuteSQL' on the GDAL/OGR data set and will result in the creation of a
new layer (and layer
is ignored). See 'OGRSQL'
https://gdal.org/user/ogr_sql_dialect.html for details. Please note that the
'FID' special field is driverdependent, and may be either 0based (e.g. ESRI
Shapefile), 1based (e.g. MapInfo) or arbitrary (e.g. OSM). Other features of
OGRSQL are also likely to be driver dependent. The available layer names may
be obtained with
st_layers. Care will be required to properly escape the use of some layer names.
read_sf
and write_sf
are aliases for st_read
and st_write
, respectively, with some
modified default arguments.
read_sf
and write_sf
are quiet by default: they do not print information
about the data source. read_sf
returns an sftibble rather than an sfdata.frame.
write_sf
delete layers by default: it overwrites existing files without asking or warning.
if table
is not given but query
is, the spatial
reference system (crs) of the table queried is only available in case it
has been stored into each geometry record (e.g., by PostGIS, when using
EWKB)
The function will automatically find the geometry
type columns for
drivers that support it. For the other drivers, it will try to cast all the
character columns, which can be slow for very wide tables.
object of class sf when a layer was successfully read; in case
argument layer
is missing and data source dsn
does not
contain a single layer, an object of class sf_layers
is returned
with the layer names, each with their geometry type(s). Note that the
number of layers may also be zero.
The use of system.file
in examples make sure that examples run regardless where R is installed:
typical users will not use system.file
but give the file name directly, either with full path or relative
to the current working directory (see getwd). "Shapefiles" consist of several files with the same basename
that reside in the same directory, only one of them having extension .shp
.
nc = st_read(system.file("shape/nc.shp", package="sf"))
summary(nc) # note that AREA was computed using Euclidian area on lon/lat degrees
## only three fields by select clause
## only two features by where clause
nc_sql = st_read(system.file("shape/nc.shp", package="sf"),
query = "SELECT NAME, SID74, FIPS FROM \"nc\" WHERE BIR74 > 20000")
## Not run:
library(sp)
example(meuse, ask = FALSE, echo = FALSE)
try(st_write(st_as_sf(meuse), "PG:dbname=postgis", "meuse",
layer_options = "OVERWRITE=true"))
try(st_meuse < st_read("PG:dbname=postgis", "meuse"))
if (exists("st_meuse"))
summary(st_meuse)
## End(Not run)
## Not run:
## note that we need special escaping of layer within single quotes (nc.gpkg)
## and that geom needs to be included in the select, otherwise we don't detect it
layer < st_layers(system.file("gpkg/nc.gpkg", package = "sf"))$name[1]
nc_gpkg_sql = st_read(system.file("gpkg/nc.gpkg", package = "sf"),
query = sprintf("SELECT NAME, SID74, FIPS, geom FROM \"%s\" WHERE BIR74 > 20000", layer))
## End(Not run)
# spatial filter, as wkt:
wkt = st_as_text(st_geometry(nc[1,]))
# filter by (bbox overlaps of) first feature geometry:
st_read(system.file("gpkg/nc.gpkg", package="sf"), wkt_filter = wkt)
# read geojson from string:
geojson_txt < paste("{\"type\":\"MultiPoint\",\"coordinates\":",
"[[3.2,4],[3,4.6],[3.8,4.4],[3.5,3.8],[3.4,3.6],[3.9,4.5]]}")
x = st_read(geojson_txt)
x
## Not run:
library(RPostgreSQL)
try(conn < dbConnect(PostgreSQL(), dbname = "postgis"))
if (exists("conn") && !inherits(conn, "tryerror")) {
x = st_read(conn, "meuse", query = "select * from meuse limit 3;")
x = st_read(conn, table = "public.meuse")
print(st_crs(x)) # SRID resolved by the database, not by GDAL!
dbDisconnect(conn)
}
## End(Not run)
Compute DE9IM relation between pairs of geometries, or match it to a given pattern
st_relate(x, y, pattern = NA_character_, sparse = !is.na(pattern))
x 
object of class 
y 
object of class 
pattern 
character; define the pattern to match to, see details. 
sparse 
logical; should a sparse matrix be returned ( 
In case pattern
is not given, st_relate
returns a dense character
matrix; element [i,j]
has nine characters, referring to the DE9IM relationship between x[i]
and y[j]
, encoded as IxIy,IxBy,IxEy,BxIy,BxBy,BxEy,ExIy,ExBy,ExEy where I refers to interior, B to boundary, and E to exterior, and e.g. BxIy the dimensionality of the intersection of the the boundary of x[i]
and the interior of y[j]
, which is one of: 0, 1, 2, or F; digits denoting dimensionality of intersection, F denoting no intersection. When pattern
is given, a dense logical matrix or sparse index list returned with matches to the given pattern; see st_intersection for a description of the returned matrix or list. See also https://en.wikipedia.org/wiki/DE9IM for further explanation.
p1 = st_point(c(0,0))
p2 = st_point(c(2,2))
pol1 = st_polygon(list(rbind(c(0,0),c(1,0),c(1,1),c(0,1),c(0,0))))  0.5
pol2 = pol1 + 1
pol3 = pol1 + 2
st_relate(st_sfc(p1, p2), st_sfc(pol1, pol2, pol3))
sfc = st_sfc(st_point(c(0,0)), st_point(c(3,3)))
grd = st_make_grid(sfc, n = c(3,3))
st_intersects(grd)
st_relate(grd, pattern = "****1****") # sides, not corners, internals
st_relate(grd, pattern = "****0****") # only corners touch
st_rook = function(a, b = a) st_relate(a, b, pattern = "F***1****")
st_rook(grd)
# queen neighbours, see \url{https://github.com/rspatial/sf/issues/234#issuecomment300511129}
st_queen < function(a, b = a) st_relate(a, b, pattern = "F***T****")
Sample points on or in (sets of) spatial features.
By default, returns a prespecified number of points that is equal to
size
(if type = "random"
and exact = TRUE
) or an approximation of
size
otherwise. spatstat
methods are
interfaced and do not use the size
argument, see examples.
st_sample(x, size, ...)
## S3 method for class 'sf'
st_sample(x, size, ...)
## S3 method for class 'sfc'
st_sample(
x,
size,
...,
type = "random",
exact = TRUE,
warn_if_not_integer = TRUE,
by_polygon = FALSE,
progress = FALSE,
force = FALSE
)
## S3 method for class 'sfg'
st_sample(x, size, ...)
## S3 method for class 'bbox'
st_sample(
x,
size,
...,
great_circles = FALSE,
segments = units::set_units(2, "degree", mode = "standard")
)
x 
object of class 
size 
sample size(s) requested; either total size, or a numeric vector with sample sizes for each feature geometry. When sampling polygons, the returned sampling size may differ from the requested size, as the bounding box is sampled, and sampled points intersecting the polygon are returned. 
... 
passed on to sample for 
type 
character; indicates the spatial sampling type; one of 
exact 
logical; should the length of output be exactly 
warn_if_not_integer 
logical; if 
by_polygon 
logical; for 
progress 
logical; if 
force 
logical; if 
great_circles 
logical; if 
segments 
units, or numeric (degrees); segment sizes for segmenting a bounding box polygon if 
The function is vectorised: it samples size
points across all geometries in
the object if size
is a single number, or the specified number of points
in each feature if size
is a vector of integers equal in length to the geometry
of x
.
if x
has dimension 2 (polygons) and geographical coordinates (long/lat), uniform random sampling on the sphere is applied, see e.g. https://mathworld.wolfram.com/SpherePointPicking.html.
For regular
or hexagonal
sampling of polygons, the resulting size is only an approximation.
As parameter called offset
can be passed to control ("fix") regular or hexagonal sampling: for polygons a length 2 numeric vector (by default: a random point from st_bbox(x)
); for lines use a number like runif(1)
.
Fibonacci sampling see: Alvaro Gonzalez, 2010. Measurement of Areas on a Sphere Using Fibonacci and LatitudeLongitude Lattices. Mathematical Geosciences 42(1), p. 4964
For regular sampling on the sphere, see also geosphere::regularCoordinates
.
Sampling methods from package spatstat
are interfaced (see examples), and need their own parameters to be set.
For instance, to use spatstat.random::rThomas()
, set type = "Thomas"
.
For sampling polygons one can specify oriented=TRUE
to make sure that polygons larger than half the globe are not reverted, e.g. when specifying a polygon from a bounding box of a global dataset. The st_sample
method for bbox
does this by default.
an sfc
object containing the sampled POINT
geometries
nc = st_read(system.file("shape/nc.shp", package="sf"))
p1 = st_sample(nc[1:3, ], 6)
p2 = st_sample(nc[1:3, ], 1:3)
plot(st_geometry(nc)[1:3])
plot(p1, add = TRUE)
plot(p2, add = TRUE, pch = 2)
x = st_sfc(st_polygon(list(rbind(c(0,0),c(90,0),c(90,90),c(0,90),c(0,0)))), crs = st_crs(4326))
plot(x, axes = TRUE, graticule = TRUE)
if (sf_extSoftVersion()["proj.4"] >= "4.9.0")
plot(p < st_sample(x, 1000), add = TRUE)
if (require(lwgeom, quietly = TRUE)) { # for st_segmentize()
x2 = st_transform(st_segmentize(x, 1e4), st_crs("+proj=ortho +lat_0=30 +lon_0=45"))
g = st_transform(st_graticule(), st_crs("+proj=ortho +lat_0=30 +lon_0=45"))
plot(x2, graticule = g)
if (sf_extSoftVersion()["proj.4"] >= "4.9.0") {
p2 = st_transform(p, st_crs("+proj=ortho +lat_0=30 +lon_0=45"))
plot(p2, add = TRUE)
}
}
x = st_sfc(st_polygon(list(rbind(c(0,0),c(90,0),c(90,10),c(0,90),c(0,0))))) # NOT long/lat:
plot(x)
p_exact = st_sample(x, 1000, exact = TRUE)
p_not_exact = st_sample(x, 1000, exact = FALSE)
length(p_exact); length(p_not_exact)
plot(st_sample(x, 1000), add = TRUE)
x = st_sfc(st_polygon(list(rbind(c(180,90),c(180,90),c(180,90),c(180,90),c(180,90)))),
crs=st_crs(4326))
# FIXME:
#if (sf_extSoftVersion()["proj.4"] >= "4.9.0") {
# p = st_sample(x, 1000)
# st_sample(p, 3)
#}
# hexagonal:
sfc = st_sfc(st_polygon(list(rbind(c(0,0), c(1,0), c(1,1), c(0,0)))))
plot(sfc)
h = st_sample(sfc, 100, type = "hexagonal")
h1 = st_sample(sfc, 100, type = "hexagonal")
plot(h, add = TRUE)
plot(h1, col = 'red', add = TRUE)
c(length(h), length(h1)) # approximate!
pt = st_multipoint(matrix(1:20,,2))
ls = st_sfc(st_linestring(rbind(c(0,0),c(0,1))),
st_linestring(rbind(c(0,0),c(.1,0))),
st_linestring(rbind(c(0,1),c(.1,1))),
st_linestring(rbind(c(2,2),c(2,2.00001))))
st_sample(ls, 80)
plot(st_sample(ls, 80))
# spatstat example:
if (require(spatstat.random)) {
x < sf::st_sfc(sf::st_polygon(list(rbind(c(0, 0), c(10, 0), c(10, 10), c(0, 0)))))
# for spatstat.random::rThomas(), set type = "Thomas":
pts < st_sample(x, kappa = 1, mu = 10, scale = 0.1, type = "Thomas")
}
bbox = st_bbox(
c(xmin = 0, xmax = 40, ymax = 70, ymin = 60),
crs = st_crs('OGC:CRS84')
)
set.seed(13531)
s1 = st_sample(bbox, 400)
st_bbox(s1) # within bbox
s2 = st_sample(bbox, 400, great_circles = TRUE)
st_bbox(s2) # outside bbox
All longitudes < 0 are added to 360, to avoid for instance parts of Alaska
being represented on the far left and right of a plot because they have
values straddling 180 degrees. In general, using a projected
coordinate reference system is to be preferred, but this method permits a
geographical coordinate reference system to be used. This is the sf
equivalent of recenter in the sp package and
ST_ShiftLongitude
in PostGIS.
st_shift_longitude(x)
## S3 method for class 'sfc'
st_shift_longitude(x, ...)
## S3 method for class 'sf'
st_shift_longitude(x, ...)
x 
object of class 
... 
ignored 
## sfc
pt1 = st_point(c(170, 50))
pt2 = st_point(c(170, 50))
(sfc = st_sfc(pt1, pt2))
sfc = st_set_crs(sfc, 4326)
st_shift_longitude(sfc)
## sf
d = st_as_sf(data.frame(id = 1:2, geometry = sfc))
st_shift_longitude(d)
Transform or convert coordinates of simple feature
st_can_transform(src, dst)
st_transform(x, crs, ...)
## S3 method for class 'sfc'
st_transform(
x,
crs = st_crs(x),
...,
aoi = numeric(0),
pipeline = character(0),
reverse = FALSE,
desired_accuracy = 1,
allow_ballpark = TRUE,
partial = TRUE,
check = FALSE
)
## S3 method for class 'sf'
st_transform(x, crs = st_crs(x), ...)
## S3 method for class 'sfg'
st_transform(x, crs = st_crs(x), ...)
st_wrap_dateline(x, options, quiet)
## S3 method for class 'sfc'
st_wrap_dateline(x, options = "WRAPDATELINE=YES", quiet = TRUE)
## S3 method for class 'sf'
st_wrap_dateline(x, options = "WRAPDATELINE=YES", quiet = TRUE)
## S3 method for class 'sfg'
st_wrap_dateline(x, options = "WRAPDATELINE=YES", quiet = TRUE)
sf_proj_info(type = "proj", path)
src 
source crs 
dst 
destination crs 
x 
object of class sf, sfc or sfg 
crs 
target coordinate reference system: object of class 
... 
ignored 
aoi 
area of interest, in degrees: WestLongitude, SouthLatitude, EastLongitude, NorthLatitude 
pipeline 
character; coordinate operation pipeline, for overriding the default operation 
reverse 
boolean; has only an effect when 
desired_accuracy 
numeric; Only coordinate operations that offer an accuracy of at least the one specified will be considered; a negative value disables this feature (requires GDAL >= 3.3) 
allow_ballpark 
logical; are ballpark (low accuracy) transformations allowed? (requires GDAL >= 3.3) 
partial 
logical; allow for partial projection, if not all points of a geometry can be projected (corresponds to setting environment variable 
check 
logical; if 
options 
character; should have "WRAPDATELINE=YES" to function; another parameter that is used is "DATELINEOFFSET=10" (where 10 is the default value) 
quiet 
logical; print options after they have been parsed? 
type 
character; one of 
path 
character; PROJ search path to be set 
st_can_transform
returns a boolean indicating whether
coordinates with CRS src can be transformed into CRS dst
Transforms coordinates of object to new projection.
Features that cannot be transformed are returned as empty geometries.
Transforms using the pipeline=
argument may fail if there is
ambiguity in the axis order of the specified coordinate reference system;
if you need the traditional GIS order, use "OGC:CRS84"
, not
"EPSG:4326"
. Extra care is needed with the ESRI Shapefile format,
because WKT1 does not store axis order unambiguously.
The st_transform
method for sfg
objects assumes that the CRS of the object is available as an attribute of that name.
For a discussion of using options
, see https://github.com/rspatial/sf/issues/280 and https://github.com/rspatial/sf/issues/1983
sf_proj_info
lists the available projections, ellipses, datums, units, or data search path of the PROJ library when type
is equal to proj, ellps, datum, units or path; when type
equals have_datum_files
a boolean is returned indicating whether datum files are installed and accessible (checking for conus
). path
returns the PROJ_INFO.searchpath
field directly, as a single string with path separaters (:
or ;
).
for PROJ >= 6, sf_proj_info
does not provide option type = "datums"
.
PROJ < 6 does not provide the option type = "prime_meridians"
.
for PROJ >= 7.1.0, the "units" query of sf_proj_info
returns the to_meter
variable as numeric, previous versions return a character vector containing a numeric expression.
st_transform_proj, part of package lwgeom.
sf_project projects a matrix of coordinates, bypassing GDAL altogether
p1 = st_point(c(7,52))
p2 = st_point(c(30,20))
sfc = st_sfc(p1, p2, crs = 4326)
sfc
st_transform(sfc, 3857)
st_transform(st_sf(a=2:1, geom=sfc), "+init=epsg:3857")
if (sf_extSoftVersion()["GDAL"] >= "3.0.0") {
st_transform(sfc, pipeline =
"+proj=pipeline +step +proj=axisswap +order=2,1") # reverse axes
st_transform(sfc, pipeline =
"+proj=pipeline +step +proj=axisswap +order=2,1", reverse = TRUE) # also reverse axes
}
nc = st_read(system.file("shape/nc.shp", package="sf"))
st_area(nc[1,]) # area from long/lat
st_area(st_transform(nc[1,], 32119)) # NC state plane, m
st_area(st_transform(nc[1,], 2264)) # NC state plane, US foot
library(units)
set_units(st_area(st_transform(nc[1,], 2264)), m^2)
st_transform(structure(p1, proj4string = "+init=epsg:4326"), "+init=epsg:3857")
st_wrap_dateline(st_sfc(st_linestring(rbind(c(179,0),c(179,0))), crs = 4326))
sf_proj_info("datum")
Create viewport from sf, sfc or sfg object
st_viewport(x, ..., bbox = st_bbox(x), asp)
x 
object of class sf, sfc or sfg object 
... 
parameters passed on to viewport 
bbox 
the bounding box used for aspect ratio 
asp 
numeric; target aspect ratio (y/x), see Details 
parameters width
, height
, xscale
and yscale
are set such that aspect ratio is honoured and plot size is maximized in the current viewport; others can be passed as ...
If asp
is missing, it is taken as 1, except when isTRUE(st_is_longlat(x))
, in which case it is set to 1.0 /cos(y)
, with y
the middle of the latitude bounding box.
The output of the call to viewport
library(grid)
nc = st_read(system.file("shape/nc.shp", package="sf"))
grid.newpage()
pushViewport(viewport(width = 0.8, height = 0.8))
pushViewport(st_viewport(nc))
invisible(lapply(st_geometry(nc), function(x) grid.draw(st_as_grob(x, gp = gpar(fill = 'red')))))
Write simple features object to file or database
st_write(obj, dsn, layer, ...)
## S3 method for class 'sfc'
st_write(obj, dsn, layer, ...)
## S3 method for class 'sf'
st_write(
obj,
dsn,
layer = NULL,
...,
driver = guess_driver_can_write(dsn),
dataset_options = NULL,
layer_options = NULL,
quiet = FALSE,
factorsAsCharacter = TRUE,
append = NA,
delete_dsn = FALSE,
delete_layer = !is.na(append) && !append,
fid_column_name = NULL,
config_options = character(0)
)
## S3 method for class 'data.frame'
st_write(obj, dsn, layer = NULL, ...)
write_sf(..., quiet = TRUE, append = FALSE, delete_layer = !append)
st_delete(
dsn,
layer = character(0),
driver = guess_driver_can_write(dsn),
quiet = FALSE
)
obj 
object of class 
dsn 
data source name. Interpretation varies by driver: can be
a filename, a folder, a database name, or a Database Connection
(we officially test support for

layer 
layer name. Varies by driver, may be a file name without
extension; for database connection, it is the name of the table. If layer
is missing, the 
... 
other arguments passed to dbWriteTable when 
driver 
character; name of driver to be used; if missing and 
dataset_options 
character; driver dependent dataset creation options; multiple options supported. 
layer_options 
character; driver dependent layer creation options; multiple options supported. 
quiet 
logical; suppress info on name, driver, size and spatial reference 
factorsAsCharacter 
logical; convert 
append 
logical; should we append to an existing layer, or replace it?
if 
delete_dsn 
logical; delete data source 
delete_layer 
logical; delete layer 
fid_column_name 
character, name of column with feature IDs; if specified, this column is no longer written as feature attribute. 
config_options 
character, named vector with GDAL config options 
Columns (variables) of a class not supported are dropped with a warning.
When updating an existing layer, records are appended to it if the updating object has the right variable names and types. If names don't match an error is raised. If types don't match, behaviour is undefined: GDAL may raise warnings or errors or fail silently.
When deleting layers or data sources is not successful, no error is emitted.
delete_dsn
and delete_layer
should be
handled with care; the former may erase complete directories or databases.
st_delete()
deletes layer(s) in a data source, or a data source if layers are
omitted; it returns TRUE
on success, FALSE
on failure, invisibly.
obj
, invisibly
nc = st_read(system.file("shape/nc.shp", package="sf"))
st_write(nc, paste0(tempdir(), "/", "nc.shp"))
st_write(nc, paste0(tempdir(), "/", "nc.shp"), delete_layer = TRUE) # overwrites
if (require(sp, quietly = TRUE)) {
data(meuse, package = "sp") # loads data.frame from sp
meuse_sf = st_as_sf(meuse, coords = c("x", "y"), crs = 28992)
# writes X and Y as columns:
st_write(meuse_sf, paste0(tempdir(), "/", "meuse.csv"), layer_options = "GEOMETRY=AS_XY")
st_write(meuse_sf, paste0(tempdir(), "/", "meuse.csv"), layer_options = "GEOMETRY=AS_WKT",
delete_dsn=TRUE) # overwrites
## Not run:
library(sp)
example(meuse, ask = FALSE, echo = FALSE)
try(st_write(st_as_sf(meuse), "PG:dbname=postgis", "meuse_sf",
layer_options = c("OVERWRITE=yes", "LAUNDER=true")))
demo(nc, ask = FALSE)
try(st_write(nc, "PG:dbname=postgis", "sids", layer_options = "OVERWRITE=true"))
## End(Not run)
}
Return 'z' range of a simple feature or simple feature set
## S3 method for class 'z_range'
is.na(x)
st_z_range(obj, ...)
## S3 method for class 'POINT'
st_z_range(obj, ...)
## S3 method for class 'MULTIPOINT'
st_z_range(obj, ...)
## S3 method for class 'LINESTRING'
st_z_range(obj, ...)
## S3 method for class 'POLYGON'
st_z_range(obj, ...)
## S3 method for class 'MULTILINESTRING'
st_z_range(obj, ...)
## S3 method for class 'MULTIPOLYGON'
st_z_range(obj, ...)
## S3 method for class 'GEOMETRYCOLLECTION'
st_z_range(obj, ...)
## S3 method for class 'MULTISURFACE'
st_z_range(obj, ...)
## S3 method for class 'MULTICURVE'
st_z_range(obj, ...)
## S3 method for class 'CURVEPOLYGON'
st_z_range(obj, ...)
## S3 method for class 'COMPOUNDCURVE'
st_z_range(obj, ...)
## S3 method for class 'POLYHEDRALSURFACE'
st_z_range(obj, ...)
## S3 method for class 'TIN'
st_z_range(obj, ...)
## S3 method for class 'TRIANGLE'
st_z_range(obj, ...)
## S3 method for class 'CIRCULARSTRING'
st_z_range(obj, ...)
## S3 method for class 'sfc'
st_z_range(obj, ...)
## S3 method for class 'sf'
st_z_range(obj, ...)
## S3 method for class 'numeric'
st_z_range(obj, ..., crs = NA_crs_)
NA_z_range_
x 
object of class 
obj 
object to compute the z range from 
... 
ignored 
crs 
object of class 
An object of class z_range
of length 2.
NA_z_range_
represents the missing value for a z_range
object
a numeric vector of length two, with zmin
and zmax
values;
if obj
is of class sf
or sfc
the object
returned has a class z_range
a = st_sf(a = 1:2, geom = st_sfc(st_point(0:2), st_point(1:3)), crs = 4326)
st_z_range(a)
st_z_range(c(zmin = 16.1, zmax = 16.6), crs = st_crs(4326))
Drop Z and/or M dimensions from feature geometries, resetting classes appropriately
st_zm(x, ..., drop = TRUE, what = "ZM")
x 
object of class 
... 
ignored 
drop 
logical; drop, or ( 
what 
character which dimensions to drop or add 
Only combinations drop=TRUE
, what = "ZM"
, and drop=FALSE
, what="Z"
are supported so far.
In case add=TRUE
, x
should have XY
geometry, and zero values are added for Z
.
st_zm(st_linestring(matrix(1:32,8)))
x = st_sfc(st_linestring(matrix(1:32,8)), st_linestring(matrix(1:8,2)))
st_zm(x)
a = st_sf(a = 1:2, geom=x)
st_zm(a)
Summarize simple feature column
## S3 method for class 'sfc'
summary(object, ..., maxsum = 7L, maxp4s = 10L)
object 
object of class 
... 
ignored 
maxsum 
maximum number of classes to summarize the simple feature column to 
maxp4s 
maximum number of characters to print from the PROJ string 
Summarize simple feature type for tibble
Summarize simple feature item for tibble
type_sum.sfc(x, ...)
obj_sum.sfc(x)
pillar_shaft.sfc(x, ...)
x 
object of class sfc 
... 
ignored 
see type_sum
Tidyverse methods for sf objects. Geometries are sticky, use as.data.frame to let dplyr
's own methods drop them. Use these methods without the .sf suffix and after loading the tidyverse package with the generic (or after loading package tidyverse).
filter.sf(.data, ..., .dots)
arrange.sf(.data, ..., .dots)
group_by.sf(.data, ..., add = FALSE)
ungroup.sf(x, ...)
rowwise.sf(x, ...)
mutate.sf(.data, ..., .dots)
transmute.sf(.data, ..., .dots)
select.sf(.data, ...)
rename.sf(.data, ...)
rename_with.sf(.data, .fn, .cols, ...)
slice.sf(.data, ..., .dots)
summarise.sf(.data, ..., .dots, do_union = TRUE, is_coverage = FALSE)
distinct.sf(.data, ..., .keep_all = FALSE)
gather.sf(
data,
key,
value,
...,
na.rm = FALSE,
convert = FALSE,
factor_key = FALSE
)
pivot_longer.sf(
data,
cols,
names_to = "name",
names_prefix = NULL,
names_sep = NULL,
names_pattern = NULL,
names_ptypes = NULL,
names_transform = NULL,
names_repair = "check_unique",
values_to = "value",
values_drop_na = FALSE,
values_ptypes = NULL,
values_transform = NULL,
...
)
pivot_wider.sf(
data,
...,
id_cols = NULL,
id_expand = FALSE,
names_from = name,
names_prefix = "",
names_sep = "_",
names_glue = NULL,
names_sort = FALSE,
names_vary = "fastest",
names_expand = FALSE,
names_repair = "check_unique",
values_from = value,
values_fill = NULL,
values_fn = NULL,
unused_fn = NULL
)
spread.sf(
data,
key,
value,
fill = NA,
convert = FALSE,
drop = TRUE,
sep = NULL
)
sample_n.sf(tbl, size, replace = FALSE, weight = NULL, .env = parent.frame())
sample_frac.sf(
tbl,
size = 1,
replace = FALSE,
weight = NULL,
.env = parent.frame()
)
group_split.sf(.tbl, ..., .keep = TRUE)
nest.sf(.data, ...)
separate.sf(
data,
col,
into,
sep = "[^[:alnum:]]+",
remove = TRUE,
convert = FALSE,
extra = "warn",
fill = "warn",
...
)
separate_rows.sf(data, ..., sep = "[^[:alnum:]]+", convert = FALSE)
unite.sf(data, col, ..., sep = "_", remove = TRUE)
unnest.sf(data, ..., .preserve = NULL)
drop_na.sf(x, ...)
inner_join.sf(x, y, by = NULL, copy = FALSE, suffix = c(".x", ".y"), ...)
left_join.sf(x, y, by = NULL, copy = FALSE, suffix = c(".x", ".y"), ...)
right_join.sf(x, y, by = NULL, copy = FALSE, suffix = c(".x", ".y"), ...)
full_join.sf(x, y, by = NULL, copy = FALSE, suffix = c(".x", ".y"), ...)
semi_join.sf(x, y, by = NULL, copy = FALSE, suffix = c(".x", ".y"), ...)
anti_join.sf(x, y, by = NULL, copy = FALSE, suffix = c(".x", ".y"), ...)
.data 
data object of class sf 
... 
other arguments 
.dots 
see corresponding function in package 
add 
see corresponding function in dplyr 
x , y

A pair of data frames, data frame extensions (e.g. a tibble), or lazy data frames (e.g. from dbplyr or dtplyr). See Methods, below, for more details. 
.fn , .cols

see original docs 
do_union 
logical; in case 
is_coverage 
logical; if 
.keep_all 
see corresponding function in dplyr 
data 
see original function docs 
key 
see original function docs 
value 
see original function docs 
na.rm 
see original function docs 
convert 
see separate_rows 
factor_key 
see original function docs 
cols 
see original function docs 
names_to 
see original function docs 
names_prefix 
see original function docs 
names_sep 
see original function docs 
names_pattern 
see original function docs 
names_ptypes 
see original function docs 
names_transform 
see original function docs 
names_repair 
see original function docs 
values_to 
see original function docs 
values_drop_na 
see original function docs 
values_ptypes 
see original function docs 
values_transform 
see original function docs 
id_cols 
see original function docs 
id_expand 
see original function docs 
names_from 
see original function docs 
names_glue 
see original function docs 
names_sort 
see original function docs 
names_vary 
see original function docs 
names_expand 
see original function docs 
values_from 
see original function docs 
values_fill 
see original function docs 
values_fn 
see original function docs 
unused_fn 
see original function docs 
fill 
see original function docs 
drop 
see original function docs 
sep 
see separate_rows 
tbl 
see original function docs 
size 
see original function docs 
replace 
see original function docs 
weight 
see original function docs 
.env 
see original function docs 
.tbl 
see original function docs 
.keep 
see original function docs 
col 
see separate 
into 
see separate 
remove 
see separate 
extra 
see separate 
.preserve 
see unnest 
by 
A join specification created with If To join on different variables between To join by multiple variables, use a
For simple equality joins, you can alternatively specify a character vector
of variable names to join by. For example, To perform a crossjoin, generating all combinations of 
copy 
If 
suffix 
If there are nonjoined duplicate variables in 
select
keeps the geometry regardless whether it is selected or not; to deselect it, first pipe through as.data.frame
to let dplyr's own select
drop it.
In case one or more of the arguments (expressions) in the summarise
call creates a geometry listcolumn, the first of these will be the (active) geometry of the returned object. If this is not the case, a geometry column is created, depending on the value of do_union
.
In case do_union
is FALSE
, summarise
will simply combine geometries using c.sfg. When polygons sharing a boundary are combined, this leads to geometries that are invalid; see for instance https://github.com/rspatial/sf/issues/681.
distinct
gives distinct records for which all attributes and geometries are distinct; st_equals is used to find out which geometries are distinct.
nest
assumes that a simple feature geometry listcolumn was among the columns that were nested.
an object of class sf
if (require(dplyr, quietly = TRUE)) {
nc = read_sf(system.file("shape/nc.shp", package="sf"))
nc %>% filter(AREA > .1) %>% plot()
# plot 10 smallest counties in grey:
st_geometry(nc) %>% plot()
nc %>% select(AREA) %>% arrange(AREA) %>% slice(1:10) %>% plot(add = TRUE, col = 'grey')
title("the ten counties with smallest area")
nc2 < nc %>% mutate(area10 = AREA/10)
nc %>% slice(1:2)
}
# plot 10 smallest counties in grey:
if (require(dplyr, quietly = TRUE)) {
st_geometry(nc) %>% plot()
nc %>% select(AREA) %>% arrange(AREA) %>% slice(1:10) %>% plot(add = TRUE, col = 'grey')
title("the ten counties with smallest area")
}
if (require(dplyr, quietly = TRUE)) {
nc$area_cl = cut(nc$AREA, c(0, .1, .12, .15, .25))
nc %>% group_by(area_cl) %>% class()
}
if (require(dplyr, quietly = TRUE)) {
nc2 < nc %>% mutate(area10 = AREA/10)
}
if (require(dplyr, quietly = TRUE)) {
nc %>% transmute(AREA = AREA/10) %>% class()
}
if (require(dplyr, quietly = TRUE)) {
nc %>% select(SID74, SID79) %>% names()
nc %>% select(SID74, SID79) %>% class()
}
if (require(dplyr, quietly = TRUE)) {
nc2 < nc %>% rename(area = AREA)
}
if (require(dplyr, quietly = TRUE)) {
nc %>% slice(1:2)
}
if (require(dplyr, quietly = TRUE)) {
nc$area_cl = cut(nc$AREA, c(0, .1, .12, .15, .25))
nc.g < nc %>% group_by(area_cl)
nc.g %>% summarise(mean(AREA))
nc.g %>% summarise(mean(AREA)) %>% plot(col = grey(3:6 / 7))
nc %>% as.data.frame %>% summarise(mean(AREA))
}
if (require(dplyr, quietly = TRUE)) {
nc[c(1:100, 1:10), ] %>% distinct() %>% nrow()
}
if (require(tidyr, quietly = TRUE) && require(dplyr, quietly = TRUE) && "geometry" %in% names(nc)) {
nc %>% select(SID74, SID79) %>% gather("VAR", "SID", geometry) %>% summary()
}
if (require(tidyr, quietly = TRUE) && require(dplyr, quietly = TRUE) && "geometry" %in% names(nc)) {
nc$row = 1:100 # needed for spread to work
nc %>% select(SID74, SID79, geometry, row) %>%
gather("VAR", "SID", geometry, row) %>%
spread(VAR, SID) %>% head()
}
if (require(tidyr, quietly = TRUE) && require(dplyr, quietly = TRUE)) {
storms.sf = st_as_sf(storms, coords = c("long", "lat"), crs = 4326)
x < storms.sf %>% group_by(name, year) %>% nest
trs = lapply(x$data, function(tr) st_cast(st_combine(tr), "LINESTRING")[[1]]) %>%
st_sfc(crs = 4326)
trs.sf = st_sf(x[,1:2], trs)
plot(trs.sf["year"], axes = TRUE)
}
Can be used to create or modify attribute variables; for transforming geometries see
st_transform, and all other functions starting with st_
.
## S3 method for class 'sf'
transform(`_data`, ...)
_data 
object of class 
... 
Further arguments of the form new_variable=expression 
a = data.frame(x1 = 1:3, x2 = 5:7)
st_geometry(a) = st_sfc(st_point(c(0,0)), st_point(c(1,1)), st_point(c(2,2)))
transform(a, x1_sq = x1^2)
transform(a, x1_x2 = x1*x2)
Checks whether a geometry is valid, or makes an invalid geometry valid
st_is_valid(x, ...)
## S3 method for class 'sfc'
st_is_valid(x, ..., NA_on_exception = TRUE, reason = FALSE)
## S3 method for class 'sf'
st_is_valid(x, ...)
## S3 method for class 'sfg'
st_is_valid(x, ...)
st_make_valid(x, ...)
## S3 method for class 'sfg'
st_make_valid(x, ...)
## S3 method for class 'sfc'
st_make_valid(
x,
...,
oriented = FALSE,
s2_options = s2::s2_options(snap = s2::s2_snap_precision(1e+07), ...),
geos_method = "valid_structure",
geos_keep_collapsed = TRUE
)
x 
object of class 
... 
passed on to s2_options 
NA_on_exception 
logical; if TRUE, for polygons that would otherwise raise a GEOS error (exception, e.g. for a POLYGON having more than zero but less than 4 points, or a LINESTRING having one point) return an 
reason 
logical; if 
oriented 
logical; only relevant if 
s2_options 
only relevant if 
geos_method 
character; either "valid_linework" (Original method, combines all rings into a set of noded lines and then extracts valid polygons from that linework) or "valid_structure" (Structured method, first makes all rings valid then merges shells and subtracts holes from shells to generate valid result. Assumes that holes and shells are correctly categorized.) (requires GEOS >= 3.10.1) 
geos_keep_collapsed 
logical; When this parameter is not set to 
For projected geometries, st_make_valid
uses the lwgeom_makevalid
method also used by the PostGIS command ST_makevalid
if the GEOS version linked to is smaller than 3.8.0, and otherwise the version shipped in GEOS; for geometries having ellipsoidal coordinates s2::s2_rebuild
is being used.
if s2_options
is not specified and x
has a nonzero precision set, then this precision value will be used as the value in s2_snap_precision
, passed on to s2_options
, rather than the 1e7 default.
st_is_valid
returns a logical vector indicating for each geometries of x
whether it is valid. st_make_valid
returns an object with a topologically valid geometry.
Object of the same class as x
p1 = st_as_sfc("POLYGON((0 0, 0 10, 10 0, 10 10, 0 0))")
st_is_valid(p1)
st_is_valid(st_sfc(st_point(0:1), p1[[1]]), reason = TRUE)
library(sf)
x = st_sfc(st_polygon(list(rbind(c(0,0),c(0.5,0),c(0.5,0.5),c(0.5,0),c(1,0),c(1,1),c(0,1),c(0,0)))))
suppressWarnings(st_is_valid(x))
y = st_make_valid(x)
st_is_valid(y)
y %>% st_cast()
vctrs methods for sf objects
vec_ptype2.sfc(x, y, ...)
## Default S3 method:
vec_ptype2.sfc(x, y, ..., x_arg = "x", y_arg = "y")
## S3 method for class 'sfc'
vec_ptype2.sfc(x, y, ...)
vec_cast.sfc(x, to, ...)
## S3 method for class 'sfc'
vec_cast.sfc(x, to, ...)
## Default S3 method:
vec_cast.sfc(x, to, ...)
x , y

Vector types. 
... 
These dots are for future extensions and must be empty. 
x_arg , y_arg

Argument names for 
to 
Type to cast to. If 