s2: functions for spherical geometry, using s2 package

s2R Documentation

functions for spherical geometry, using s2 package

Description

functions for spherical geometry, using the s2 package based on the google s2geometry.io library

Usage

sf_use_s2(use_s2)

st_as_s2(x, ...)

## S3 method for class 'sf'
st_as_s2(x, ...)

## S3 method for class 'sfc'
st_as_s2(x, ..., oriented = FALSE, rebuild = FALSE)

Arguments

use_s2

logical; if TRUE, use the s2 spherical geometry package for geographical coordinate operations

x

object of class sf, sfc or sfg

...

passed on

oriented

logical; if FALSE, polygons that cover more than half of the globe are inverted; if TRUE, no reversal takes place and it is assumed that the inside of the polygon is to the left of the polygon's path.

rebuild

logical; call s2_rebuild on the geometry (think of this as a st_make_valid on the sphere)

Details

st_as_s2 converts an sf POLYGON object into a form readable by s2.

Value

sf_use_s2 returns the value of this variable before (re)setting it, invisibly if use_s2 is not missing.

Examples

m = rbind(c(-1,-1), c(1,-1), c(1,1), c(-1,1), c(-1,-1))
m1 = rbind(c(-1,-1), c(1,-1), c(1,1), c(-1,1), c(-1,0), c(-1,-1))
m0 = m[5:1,]
mp = st_multipolygon(list(
list(m, 0.8 * m0, 0.01 * m1 + 0.9),
list(0.7* m, 0.6*m0),
list(0.5 * m0),
list(m+2),
list(m+4,(.9*m0)+4)
))
sf = st_sfc(mp, mp, crs = 'EPSG:4326')
s2 = st_as_s2(sf)

sf documentation built on March 18, 2022, 5:22 p.m.