st_as_sfc: Convert foreign geometry object to an sfc object

Description Usage Arguments Details Examples

View source: R/sp.R

Description

Convert foreign geometry object to an sfc object

Usage

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## S3 method for class 'list'
st_as_sfc(x, ..., crs = NA_crs_)

## S3 method for class 'blob'
st_as_sfc(x, ...)

## S3 method for class 'bbox'
st_as_sfc(x, ...)

## S3 method for class 'WKB'
st_as_sfc(x, ..., EWKB = FALSE, spatialite = FALSE,
  pureR = FALSE, crs = NA_crs_)

## S3 method for class 'raw'
st_as_sfc(x, ...)

## S3 method for class 'character'
st_as_sfc(x, crs = NA_integer_, ...,
  GeoJSON = FALSE)

## S3 method for class 'factor'
st_as_sfc(x, ...)

st_as_sfc(x, ...)

## S3 method for class 'SpatialPoints'
st_as_sfc(x, ..., precision = 0)

## S3 method for class 'SpatialPixels'
st_as_sfc(x, ..., precision = 0)

## S3 method for class 'SpatialMultiPoints'
st_as_sfc(x, ..., precision = 0)

## S3 method for class 'SpatialLines'
st_as_sfc(x, ..., precision = 0,
  forceMulti = FALSE)

## S3 method for class 'SpatialPolygons'
st_as_sfc(x, ..., precision = 0,
  forceMulti = FALSE)

## S3 method for class 'map'
st_as_sfc(x, ...)

Arguments

x

object to convert

...

further arguments

crs

integer or character; coordinate reference system for the

EWKB

logical; if TRUE, parse as EWKB (extended WKB; PostGIS: ST_AsEWKB), otherwise as ISO WKB (PostGIS: ST_AsBinary)

spatialite

logical; if TRUE, WKB is assumed to be in the spatialite dialect, see https://www.gaia-gis.it/gaia-sins/BLOB-Geometry.html; this is only supported in native endian-ness (i.e., files written on system with the same endian-ness as that on which it is being read).

pureR

logical; if TRUE, use only R code, if FALSE, use compiled (C++) code; use TRUE when the endian-ness of the binary differs from the host machine (.Platform$endian).

GeoJSON

logical; if TRUE, try to read geometries from GeoJSON text strings geometry, see st_crs()

precision

precision value; see st_as_binary

forceMulti

logical; if TRUE, force coercion into MULTIPOLYGON or MULTILINE objects, else autodetect

Details

When converting from WKB, the object x is either a character vector such as typically obtained from PostGIS (either with leading "0x" or without), or a list with raw vectors representing the features in binary (raw) form.

If x is a character vector, it should be a vector containing well-known-text, or Postgis EWKT or GeoJSON representations of a single geometry for each vector element.

If x is a factor, it is converted to character.

Examples

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wkb = structure(list("01010000204071000000000000801A064100000000AC5C1441"), class = "WKB")
st_as_sfc(wkb, EWKB = TRUE)
wkb = structure(list("0x01010000204071000000000000801A064100000000AC5C1441"), class = "WKB")
st_as_sfc(wkb, EWKB = TRUE)
st_as_sfc(st_as_binary(st_sfc(st_point(0:1)))[[1]], crs = 4326)
st_as_sfc("SRID=3978;LINESTRING(1663106 -105415,1664320 -104617)")

sf documentation built on Sept. 17, 2019, 9:03 a.m.