choropleth: choropleth

In GISTools: Some further GIS capabilities for R

Description

Draws a choropleth map given a spatialPolygons object, a variable and a shading scheme.

Usage

choropleth(sp, v, shading = auto.shading(v), ...)

Arguments

sp	A spatialPolygons or spatialPolygonsDataFrame object.
v	The variaqble to be mapped. Must have the same number of elements as s has polygons.
shading	A shading scheme created by shading or auto.shading.
...	Additional parameters to be passed on to the plot method for sp.

Details

The function returns no value, but draws a choropleth map on the current graphics device as a side effect.

Value

None (see above).

Author(s)

Chris Brunsdon

See Also

choro.legend, auto.shading, shading.

Examples

# Read in map data and compute a rate for mapping
sids <- readShapePoly(system.file("shapes/sids.shp", package="maptools")[1], 
	proj4string=CRS("+proj=longlat +ellps=clrk66"))
sids.rate=10000*sids$SID74/sids$BIR74
# Create the shading scheme,  plot a choropleth map 
shades = auto.shading(sids.rate,cols=brewer.pal(5,'Blues'))
choropleth(sids,sids.rate,shades)

GISTools documentation built on May 6, 2019, 1:09 a.m.