leglabs: Make legend labels

In maptools: Tools for Handling Spatial Objects

Make legend labels

Description

leglabs makes character strings from the same break points. The plot.polylist() function may be used as a generic S3 method.

Usage

leglabs(vec, under="under", over="over", between="-", reverse=FALSE)

Arguments

vec	vector of break values
under	character value for under
over	character value for over
between	character value for between
reverse	flag to reverse order of values, you will also need to reorder colours, see example

Author(s)

Roger Bivand [e-mail]

See Also

findInterval

Examples

mappolys <- readShapeSpatial(system.file("shapes/columbus.shp", package="maptools")[1], ID="NEIGNO")
brks <- round(quantile(mappolys$CRIME, probs=seq(0,1,0.2)), digits=2)
colours <- c("salmon1", "salmon2", "red3", "brown", "black")
plot(mappolys, col=colours[findInterval(mappolys$CRIME, brks,
 all.inside=TRUE)])
legend(x=c(5.8, 7.1), y=c(13, 14.5), legend=leglabs(brks),
  fill=colours, bty="n")
title(main=paste("Columbus OH: residential burglaries and vehicle",
 "thefts per thousand households, 1980", sep="\n"))
#legend with reversed order
plot(mappolys, col=colours[findInterval(mappolys$CRIME, brks,
 all.inside=TRUE)])
legend(x=c(5.8, 7.1), y=c(13, 14.5), legend=leglabs(brks, reverse = TRUE),
  fill=rev(colours), bty="n")
title(main=paste("Columbus OH: residential burglaries and vehicle",
 "thefts per thousand households, 1980 (reversed legend)", sep="\n"))

maptools documentation built on July 26, 2023, 5:38 p.m.