rmapshaper (version 0.4.4)

ms_innerlines: Create a line layer consisting of shared boundaries with no attribute data

Description

Create a line layer consisting of shared boundaries with no attribute data

Usage

ms_innerlines(input, force_FC = TRUE, sys = FALSE)

Arguments

input

input polygons object to convert to inner lines. One of:

• geo_json or character polygons;

• geo_list polygons;

• SpatialPolygons*;

• sf or sfc polygons object

force_FC

should the output be forced to be a FeatureCollection even if there are no attributes? Default TRUE. FeatureCollections are more compatible with rgdal::readOGR and geojsonio::geojson_sp. If FALSE and there are no attributes associated with the geometries, a GeometryCollection will be output. Ignored for Spatial objects.

sys

Should the system mapshaper be used instead of the bundled mapshaper? Gives better performance on large files. Requires the mapshaper node package to be installed and on the PATH.

Value

lines in the same class as the input layer, but without attributes

Examples

# NOT RUN {
library(geojsonio)
library(sp)

poly <- structure('{"type":"FeatureCollection",
            "features":[
              {"type":"Feature",
                "properties":{"foo": "a"},
                "geometry":{"type":"Polygon","coordinates":[[
                  [102,2],[102,3],[103,3],[103,2],[102,2]
                  ]]}}
              ,{"type":"Feature",
                "properties":{"foo": "a"},
                "geometry":{"type":"Polygon","coordinates":[[
                  [103,3],[104,3],[104,2],[103,2],[103,3]
                  ]]}},
              {"type":"Feature",
                "properties":{"foo": "b"},
                "geometry":{"type":"Polygon","coordinates":[[
                  [102,1],[102,2],[103,2],[103,1],[102,1]
                  ]]}},
              {"type":"Feature",
                "properties":{"foo": "b"},
                "geometry":{"type":"Polygon","coordinates":[[
                  [103,1],[103,2],[104,2],[104,1],[103,1]
                  ]]}}]}', class = c("json", "geo_json"))

poly <- geojson_sp(poly)
plot(poly)

out <- ms_innerlines(poly)
plot(out)

# }