R: Create simple feature from a numeric vector, matrix or list

st {sf} | R Documentation

## Create simple feature from a numeric vector, matrix or list

### Description

Create simple feature from a numeric vector, matrix or list

### Usage

    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, ...)

### Arguments

`x` | for `st_point`, numeric vector (or one-row-matrix) of length 2, 3 or 4; for `st_linestring` and `st_multipoint`, numeric matrix with points in rows; for `st_polygon` and `st_multilinestring`, list with numeric matrices with points in rows; for `st_multipolygon`, list of lists with numeric matrices; for `st_geometrycollection` list with (non-geometrycollection) simple feature objects
`dim` | character, indicating dimensions: "XY", "XYZ", "XYM", or "XYZM"; only really needed for three-dimensional 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 `x` is the empty `list()`.
`...` | 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 TRUE, try to simplify results; if FALSE, return geometrycollection containing all objects

### Details

"XYZ" refers to coordinates where the third dimension represents altitude, "XYM" refers to three-dimensional 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.

### Value

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.

### Examples

    (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))))

[Package sf version 1.0-7 Index]