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R version 4.0.0 (2020-04-24) -- "Arbor Day"
Copyright (C) 2020 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.
R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.
Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.
> suppressPackageStartupMessages(library(sf))
>
> # create empty geometries:
> st_point(rep(NA_real_,2))
POINT EMPTY
> st_point(rep(NA_real_,3), dim = "XYZ")
POINT Z EMPTY
> st_point(rep(NA_real_,3), dim = "XYM")
POINT M EMPTY
> st_point(rep(NA_real_,4), dim = "XYZM")
POINT ZM EMPTY
>
> st_multipoint()
MULTIPOINT EMPTY
> st_multipoint(matrix(numeric(0), 0, 3), dim = "XYZ")
MULTIPOINT Z EMPTY
> st_multipoint(matrix(numeric(0), 0, 3), dim = "XYM")
MULTIPOINT M EMPTY
> st_multipoint(matrix(numeric(0), 0, 4), dim = "XYZM")
MULTIPOINT ZM EMPTY
>
> st_linestring(matrix(numeric(0), 0, 2), "XY")
LINESTRING EMPTY
> st_linestring(matrix(numeric(0), 0, 3), "XYZ")
LINESTRING Z EMPTY
> st_linestring(matrix(numeric(0), 0, 3), "XYM")
LINESTRING M EMPTY
> st_linestring(matrix(numeric(0), 0, 4), "XYZM")
LINESTRING ZM EMPTY
>
> st_multilinestring(list(), "XY")
MULTILINESTRING EMPTY
> st_multilinestring(list(), "XYZ")
MULTILINESTRING Z EMPTY
> st_multilinestring(list(), "XYM")
MULTILINESTRING M EMPTY
> st_multilinestring(list(), "XYZM")
MULTILINESTRING ZM EMPTY
>
> st_polygon(list(), "XY")
POLYGON EMPTY
> st_polygon(list(), "XYZ")
POLYGON Z EMPTY
> st_polygon(list(), "XYM")
POLYGON M EMPTY
> st_polygon(list(), "XYZM")
POLYGON ZM EMPTY
>
> st_multipolygon(list(), "XY")
MULTIPOLYGON EMPTY
> st_multipolygon(list(), "XYZ")
MULTIPOLYGON Z EMPTY
> st_multipolygon(list(), "XYM")
MULTIPOLYGON M EMPTY
> st_multipolygon(list(), "XYZM")
MULTIPOLYGON ZM EMPTY
>
> st_geometrycollection()
GEOMETRYCOLLECTION EMPTY
> st_geometrycollection(dim = "XYZ")
GEOMETRYCOLLECTION Z EMPTY
> st_geometrycollection(dim = "XYM")
GEOMETRYCOLLECTION M EMPTY
> st_geometrycollection(dim = "XYZM")
GEOMETRYCOLLECTION ZM EMPTY
>
> st_point(rep(NA_real_,2))
POINT EMPTY
> st_multipoint()
MULTIPOINT EMPTY
> st_linestring(matrix(numeric(0), 0, 2))
LINESTRING EMPTY
> st_multilinestring(list(), "XY")
MULTILINESTRING EMPTY
> st_polygon(list(), "XY")
POLYGON EMPTY
> st_multipolygon(list(), "XY")
MULTIPOLYGON EMPTY
> st_geometrycollection(, "XY")
GEOMETRYCOLLECTION EMPTY
>
> (e1 = st_sfc(
+ st_point(rep(NA_real_,2)),
+ st_multipoint(),
+ st_linestring(matrix(numeric(0), 0, 2)),
+ st_multilinestring(list(), "XY"),
+ st_polygon(list(), "XY"),
+ st_multipolygon(list(), "XY"),
+ st_geometrycollection(, "XY")))
Geometry set for 7 features (with 7 geometries empty)
geometry type: GEOMETRY
dimension: XY
bbox: xmin: NA ymin: NA xmax: NA ymax: NA
CRS: NA
First 5 geometries:
POINT EMPTY
MULTIPOINT EMPTY
LINESTRING EMPTY
MULTILINESTRING EMPTY
POLYGON EMPTY
>
> (e2 = st_sfc(st_point(rep(NA_real_,3), "XYZ"),
+ st_multipoint(matrix(numeric(0),0,3), dim = "XYZ"),
+ st_linestring(matrix(numeric(0), 0, 3)),
+ st_multilinestring(list(), "XYZ"),
+ st_polygon(list(), "XYZ"),
+ st_multipolygon(list(), "XYZ"),
+ st_geometrycollection(dim = "XYZ")))
Geometry set for 7 features (with 7 geometries empty)
geometry type: GEOMETRY
dimension: XYZ
bbox: xmin: NA ymin: NA xmax: NA ymax: NA
z_range: zmin: NA zmax: NA
CRS: NA
First 5 geometries:
POINT Z EMPTY
MULTIPOINT Z EMPTY
LINESTRING Z EMPTY
MULTILINESTRING Z EMPTY
POLYGON Z EMPTY
>
> (e3 = st_sfc(st_point(rep(NA_real_,3), "XYM"),
+ st_multipoint(matrix(numeric(0),0,3), dim = "XYM"),
+ st_linestring(matrix(numeric(0), 0, 3), "XYM"),
+ st_multilinestring(list(), "XYM"),
+ st_polygon(list(), "XYM"),
+ st_multipolygon(list(), "XYM"),
+ st_geometrycollection(dim = "XYM")))
Geometry set for 7 features (with 7 geometries empty)
geometry type: GEOMETRY
dimension: XYM
bbox: xmin: NA ymin: NA xmax: NA ymax: NA
m_range: mmin: NA mmax: NA
CRS: NA
First 5 geometries:
POINT M EMPTY
MULTIPOINT M EMPTY
LINESTRING M EMPTY
MULTILINESTRING M EMPTY
POLYGON M EMPTY
>
> (e4 = st_sfc(st_point(rep(NA_real_,4)),
+ st_multipoint(matrix(numeric(0),0,4), dim = "XYZM"),
+ st_linestring(matrix(numeric(0), 0, 4)),
+ st_multilinestring(list(), "XYZM"),
+ st_polygon(list(), "XYZM"),
+ st_multipolygon(list(), "XYZM"),
+ st_geometrycollection(dim = "XYZM")))
Geometry set for 7 features (with 7 geometries empty)
geometry type: GEOMETRY
dimension: XYZM
bbox: xmin: NA ymin: NA xmax: NA ymax: NA
z_range: zmin: NA zmax: NA
m_range: mmin: NA mmax: NA
CRS: NA
First 5 geometries:
POINT ZM EMPTY
MULTIPOINT ZM EMPTY
LINESTRING ZM EMPTY
MULTILINESTRING ZM EMPTY
POLYGON ZM EMPTY
>
> st_as_sfc(st_as_binary(e1, pureR = TRUE))
Geometry set for 7 features (with 7 geometries empty)
geometry type: GEOMETRY
dimension: XY
bbox: xmin: NA ymin: NA xmax: NA ymax: NA
CRS: NA
First 5 geometries:
POINT EMPTY
MULTIPOINT EMPTY
LINESTRING EMPTY
MULTILINESTRING EMPTY
POLYGON EMPTY
> st_as_sfc(st_as_binary(e1, pureR = FALSE))
Geometry set for 7 features (with 7 geometries empty)
geometry type: GEOMETRY
dimension: XY
bbox: xmin: NA ymin: NA xmax: NA ymax: NA
CRS: NA
First 5 geometries:
POINT EMPTY
MULTIPOINT EMPTY
LINESTRING EMPTY
MULTILINESTRING EMPTY
POLYGON EMPTY
> st_as_sfc(st_as_binary(e2, pureR = FALSE))
Geometry set for 7 features (with 7 geometries empty)
geometry type: GEOMETRY
dimension: XYZ
bbox: xmin: NA ymin: NA xmax: NA ymax: NA
z_range: zmin: NA zmax: NA
CRS: NA
First 5 geometries:
POINT Z EMPTY
MULTIPOINT Z EMPTY
LINESTRING Z EMPTY
MULTILINESTRING Z EMPTY
POLYGON Z EMPTY
> st_as_sfc(st_as_binary(e3, pureR = FALSE))
Geometry set for 7 features (with 7 geometries empty)
geometry type: GEOMETRY
dimension: XYM
bbox: xmin: NA ymin: NA xmax: NA ymax: NA
m_range: mmin: NA mmax: NA
CRS: NA
First 5 geometries:
POINT M EMPTY
MULTIPOINT M EMPTY
LINESTRING M EMPTY
MULTILINESTRING M EMPTY
POLYGON M EMPTY
> st_as_sfc(st_as_binary(e4, pureR = FALSE))
Geometry set for 7 features (with 7 geometries empty)
geometry type: GEOMETRY
dimension: XYZM
bbox: xmin: NA ymin: NA xmax: NA ymax: NA
z_range: zmin: NA zmax: NA
m_range: mmin: NA mmax: NA
CRS: NA
First 5 geometries:
POINT ZM EMPTY
MULTIPOINT ZM EMPTY
LINESTRING ZM EMPTY
MULTILINESTRING ZM EMPTY
POLYGON ZM EMPTY
> st_as_sfc(st_as_binary(e1, pureR = FALSE))
Geometry set for 7 features (with 7 geometries empty)
geometry type: GEOMETRY
dimension: XY
bbox: xmin: NA ymin: NA xmax: NA ymax: NA
CRS: NA
First 5 geometries:
POINT EMPTY
MULTIPOINT EMPTY
LINESTRING EMPTY
MULTILINESTRING EMPTY
POLYGON EMPTY
>
> # sfc_GEOMETRY:
> x = st_sfc(st_point(0:1), st_linestring(matrix(1:4,2,2)))
> st_intersects(x, x, sparse = FALSE)
[,1] [,2]
[1,] TRUE FALSE
[2,] FALSE TRUE
>
> # two empty geoms:
> x = st_sfc(st_multipoint(), st_linestring())
> st_intersects(x, x, sparse = FALSE)
[,1] [,2]
[1,] FALSE FALSE
[2,] FALSE FALSE
>
> # write & read:
> x = st_sf(a = 2:1, geom = structure(st_sfc(st_linestring(), st_linestring(matrix(1:4,2)))))
> write_sf(x, "empty.gpkg")
> y = st_read("empty.gpkg", quiet = TRUE)
> all.equal(x, y)
[1] TRUE
>
> # https://github.com/edzer/sfr/issues/398 :
> pt = st_sfc(st_point(c(0,92)), crs = 4267)
> robin_crs <- "+proj=robin +lon_0=0 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs"
> # india_crs <- "+init=epsg:24383" # India-centered Lambert conformal conic projection
> india_crs <- "+proj=lcc +lat_1=12 +lat_0=12 +lon_0=80 +k_0=0.99878641 +x_0=2743195.5 +y_0=914398.5 +a=6377299.151 +b=6356098.145120132 +towgs84=295,736,257,0,0,0,0 +units=m +no_defs"
> st_transform(st_transform(pt, robin_crs), india_crs)[[1]]
POINT EMPTY
>
> proc.time()
user system elapsed
0.775 0.064 0.837
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