legend.gradient {SDMTools} | R Documentation |
legend.gradient
creates and displays a gradient
legend on a plot or image file. The place and size of the
legend is defined by coordinates, previously identified.
legend.gradient(pnts, cols = heat.colors(100), limits = c(0, 1), title = "Legend", ...)
pnts |
x and y coordinates of the gradient location in the plot |
cols |
a set of 2 or more colors used in the image, to create the gradient |
limits |
to label the min and max values of the gradient in the legend |
title |
to specify the title of the legend |
... |
other graphical parameters defined by image() or plot() |
nothing is returned, a gradient legend is added to a plot or a image.
Lorena Falconi lorefalconi@gmail.com
#define a simple binary matrix tmat = { matrix(c( 0,0,0,1,0,0,1,1,0,1, 0,0,1,0,1,0,0,0,0,0, 0,1,NA,1,0,1,0,0,0,1, 1,0,1,1,1,0,1,0,0,1, 0,1,0,1,0,1,0,0,0,1, 0,0,1,0,1,0,0,1,1,0, 1,0,0,1,0,0,1,0,0,0, 0,1,0,0,0,1,0,NA,NA,NA, 0,0,1,1,1,0,0,NA,NA,NA, 1,1,1,0,0,0,0,NA,NA,NA),nr=10,byrow=TRUE) } #do the connected component labeling tasc = ConnCompLabel(tmat) # Create a color ramp colormap=c("grey","yellow","yellowgreen","olivedrab1","lightblue4") #create an image image(tasc,col=colormap, axes=FALSE, xlab="", ylab="", ann=FALSE) #points for the gradient legend pnts = cbind(x =c(0.8,0.9,0.9,0.8), y =c(1.0,1.0,0.8,0.8)) #create the gradient legend legend.gradient(pnts,colormap,c("Low","High"))