Get the geometry (coordinates) of a SpatVector

Get the geometry of a SpatVector. If wkt=FALSE, this is a five-column matrix or data.frame: the vector object ID, the IDs for the parts of each object (e.g. five polygons that together are one spatial object), the x (longitude) and y (latitude) coordinates, and a flag indicating whether the part is a "hole" (only relevant for polygons).

If wkt=TRUE, the "well-known text" representation is returned as a character vector. If hex=TRUE, the "hexadecimal" representation is returned as a character vector. If wkb=TRUE, the "well-known binary" representation is returned as a list of raw vectors.

Usage

# S4 method for class 'SpatVector'
geom(x, wkt=FALSE, hex=FALSE, wkb=FALSE, df=FALSE, list=FALSE, xnm="x", ynm="y")

Arguments

x

SpatVector

wkt

logical. If TRUE the WKT geometry is returned (unless hex is also TRUE)

hex

logical. If TRUE the hexadecimal geometry is returned

wkb

logical. If TRUE the raw WKB geometry is returned (unless either of hex or wkt is also TRUE)

df

logical. If TRUE a data.frame is returned instead of a matrix (only if wkt=FALSE, hex=FALSE, and list=FALSE)

list

logical. If TRUE a nested list is returned with data.frames of coordinates

xnm

character. If list=TRUE the "x" column name for the coordinates data.frame

ynm

character. If list=TRUE the "y" column name for the coordinates data.frame

Value

matrix, vector, data.frame, or list

See also

crds, xyFromCell

Examples

x1 <- rbind(c(-175,-20), c(-140,55), c(10, 0), c(-140,-60))
x2 <- rbind(c(-125,0), c(0,60), c(40,5), c(15,-45))
x3 <- rbind(c(-10,0), c(140,60), c(160,0), c(140,-55))
x4 <- rbind(c(80,0), c(105,13), c(120,2), c(105,-13))
z <- rbind(cbind(object=1, part=1, x1), cbind(object=2, part=1, x2), 
           cbind(object=3, part=1, x3), cbind(object=3, part=2,  x4))
colnames(z)[3:4] <- c('x', 'y')
z <- cbind(z, hole=0)
z[(z[, "object"]==3 & z[,"part"]==2), "hole"] <- 1

p <- vect(z, "polygons")
geom(p)
#>       geom part    x   y hole
#>  [1,]    1    1 -175 -20    0
#>  [2,]    1    1 -140  55    0
#>  [3,]    1    1   10   0    0
#>  [4,]    1    1 -140 -60    0
#>  [5,]    1    1 -175 -20    0
#>  [6,]    2    1 -125   0    0
#>  [7,]    2    1    0  60    0
#>  [8,]    2    1   40   5    0
#>  [9,]    2    1   15 -45    0
#> [10,]    2    1 -125   0    0
#> [11,]    3    1  -10   0    0
#> [12,]    3    1  140  60    0
#> [13,]    3    1  160   0    0
#> [14,]    3    1  140 -55    0
#> [15,]    3    1  -10   0    0
#> [16,]    3    1   80   0    1
#> [17,]    3    1  105  13    1
#> [18,]    3    1  120   2    1
#> [19,]    3    1  105 -13    1
#> [20,]    3    1   80   0    1

f <- system.file("ex/lux.shp", package="terra")
v <- vect(f)
g <- geom(v)
head(g)
#>      geom part        x        y hole
#> [1,]    1    1 6.026519 50.17767    0
#> [2,]    1    1 6.031361 50.16563    0
#> [3,]    1    1 6.035646 50.16410    0
#> [4,]    1    1 6.042747 50.16157    0
#> [5,]    1    1 6.043894 50.16116    0
#> [6,]    1    1 6.048243 50.16008    0

w <- geom(v, wkt=TRUE)
substr(w, 1, 60)
#>  [1] "POLYGON ((6.0265188199999997 50.1776695300000029, 6.03136109"
#>  [2] "POLYGON ((6.1783676099999996 49.8768234300000017, 6.18547869"
#>  [3] "POLYGON ((5.8813781699999996 49.8701477099999977, 5.88167238"
#>  [4] "POLYGON ((6.1313085599999999 49.9725646999999995, 6.13429117"
#>  [5] "POLYGON ((5.9779286400000000 50.0260162399999970, 5.98231220"
#>  [6] "POLYGON ((6.3855319000000001 49.8370285000000024, 6.38859987"
#>  [7] "POLYGON ((6.3166646999999996 49.6233749399999979, 6.31834983"
#>  [8] "POLYGON ((6.4251575499999998 49.7316436799999977, 6.42656994"
#>  [9] "POLYGON ((5.9983120000000003 49.6999244699999991, 5.99863242"
#> [10] "POLYGON ((6.0394744899999999 49.4482612600000024, 6.03690576"
#> [11] "POLYGON ((6.1559634200000000 49.6850471500000026, 6.15928363"
#> [12] "POLYGON ((6.0679822000000003 49.8284645100000034, 6.07192183"