ms_filter_fields: Delete fields in the attribute table

In rmapshaper: Client for 'mapshaper' for 'Geospatial' Operations

Description

Removes all fields except those listed in the fields parameter

Usage

ms_filter_fields(input, fields)

Arguments

input	spatial object to filter fields on. One of: geo_json or character points, lines, or polygons; geo_list points, lines, or polygons; SpatialPolygonsDataFrame, SpatialLinesDataFrame, SpatialPointsDataFrame; sf object
fields	character vector of fields to retain.

Value

object with only specified attributes retained, in the same class as the input

Examples

library(geojsonio)
library(sp)

poly <- structure("{\"type\":\"FeatureCollection\",
                  \"features\":[{\"type\":\"Feature\",
                  \"properties\":{\"a\": 1, \"b\":2, \"c\": 3},
                  \"geometry\":{\"type\":\"Polygon\",
                  \"coordinates\":[[[102,2],[102,4],[104,4],[104,2],[102,2]]]}}]}",
                  class = c("json", "geo_json"))
poly <- geojson_sp(poly)
poly@data

# Filter (keep) fields a and b, drop c
out <- ms_filter_fields(poly, c("a", "b"))
out@data

rmapshaper documentation built on Aug. 16, 2017, 9:07 a.m.