geos_query: Dimension, simplicity, validity or is_empty queries on simple...

Description Usage Arguments Value Examples

Description

Dimension, simplicity, validity or is_empty queries on simple feature geometries

Usage

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st_dimension(x, NA_if_empty = TRUE)

st_is_simple(x)

st_is_empty(x)

st_is_valid(x, NA_on_exception = TRUE, reason = FALSE)

Arguments

x

object of class sf, sfc or sfg

NA_if_empty

logical; if TRUE, return NA for empty geometries

NA_on_exception

logical; if TRUE, for polygons that would otherwise raise a GEOS error (exception, e.g. for a POLYGON having more than zero but less than 4 points, or a LINESTRING having one point) return an NA rather than raising an error, and suppress warning messages (e.g. about self-intersection); if FALSE, regular GEOS errors and warnings will be emitted.

reason

logical; if TRUE, return a character with, for each geometry, the reason for invalidity, NA on exception, or "Valid Geometry" otherwise.

Value

st_dimension returns a numeric vector with 0 for points, 1 for lines, 2 for surfaces, and, if NA_if_empty is TRUE, NA for empty geometries.

st_is_simple returns a logical vector, indicating for each geometry whether it is simple (e.g., not self-intersecting)

st_is_empty returns for each geometry whether it is empty

st_is_valid returns a logical vector indicating for each geometries of x whether it is valid.

Examples

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x = st_sfc(
	st_point(0:1),
	st_linestring(rbind(c(0,0),c(1,1))),
	st_polygon(list(rbind(c(0,0),c(1,0),c(0,1),c(0,0)))),
	st_multipoint(),
	st_linestring(),
	st_geometrycollection())
st_dimension(x)
st_dimension(x, FALSE)
ls = st_linestring(rbind(c(0,0), c(1,1), c(1,0), c(0,1)))
st_is_simple(st_sfc(ls, st_point(c(0,0))))
ls = st_linestring(rbind(c(0,0), c(1,1), c(1,0), c(0,1)))
st_is_empty(st_sfc(ls, st_point(), st_linestring()))
p1 = st_as_sfc("POLYGON((0 0, 0 10, 10 0, 10 10, 0 0))")
st_is_valid(p1)
st_is_valid(st_sfc(st_point(0:1), p1[[1]]), reason = TRUE)

sf documentation built on July 24, 2019, 5:05 p.m.