Access components of a wkpool object

Extract the vertex pool, segment table, or feature vector from a wkpool.

Usage

pool_vertices(x)

pool_segments(x)

pool_feature(x)

pool_path(x)

pool_paths(x)

Arguments

x

A wkpool object.

Value

• pool_vertices(): A data frame with columns .vx (vertex ID), x, y, and optionally z.

• pool_segments(): A data frame with columns .vx0, .vx1, and optionally .feature and .path.

• pool_feature(): An integer vector of feature IDs, or NULL if no feature information is present.

• pool_path(): An integer vector of path IDs (one per segment), or NULL if no path provenance is present.

• pool_paths(): A data frame describing each path (.path, .feature, .part, .ring, as captured from wk::wk_coords() identifiers), or NULL.

Examples

x <- wk::as_wkb(c(
  "POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))",
  "POLYGON ((1 0, 2 0, 2 1, 1 1, 1 0))"
))
pool <- establish_topology(x)
pool_vertices(pool)
#>    .vx x y
#> 1    1 0 0
#> 2    2 1 0
#> 3    3 1 1
#> 4    4 0 1
#> 5    5 0 0
#> 6    6 1 0
#> 7    7 2 0
#> 8    8 2 1
#> 9    9 1 1
#> 10  10 1 0
pool_segments(pool)
#>   .vx0 .vx1 .feature .path
#> 1    1    2        1     1
#> 2    2    3        1     1
#> 3    3    4        1     1
#> 4    4    5        1     1
#> 5    6    7        2     2
#> 6    7    8        2     2
#> 7    8    9        2     2
#> 8    9   10        2     2
pool_feature(pool)
#> [1] 1 1 1 1 2 2 2 2