st_is_polygon_cw: Check if a POLYGON or MULTIPOLYGON is clockwise

Description Usage Arguments Value Examples

View source: R/clockwise.R

Description

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

Usage

1

Arguments

x

object with polygon geometries

Value

logical with length the same number of features in 'x'

Examples

1
2
3
4
5
6
7
8
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]])

lwgeom documentation built on Oct. 6, 2021, 5:12 p.m.