st_is_polygon_cw function

Check if a POLYGON or MULTIPOLYGON is clockwise

Check if a POLYGON or MULTIPOLYGON is clockwise

Check if a POLYGON or MULTIPOLYGON is clockwise. According to the 'Right-hand-rule', outer rings should be clockwise, and inner holes should be counter-clockwise

st_is_polygon_cw(x)

Arguments

  • x: object with polygon geometries

Returns

logical with length the same number of features in x

Examples

library(sf) polys <- st_sf(cw = c(FALSE, TRUE), st_as_sfc(c('POLYGON ((0 0, 1 0, 1 1, 0 0))', 'POLYGON ((1 1, 2 2, 2 1, 1 1))'))) st_is_polygon_cw(polys) st_is_polygon_cw(st_geometry(polys)) st_is_polygon_cw(st_geometry(polys)[[1]])