Legend Gradient

Description

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.

Usage

legend.gradient(pnts, cols = heat.colors(100), limits = c(0, 1),
  title = "Legend", ...)

Arguments

Value

nothing is returned, a gradient legend is added to a plot or a image.

Author(s)

Lorena Falconi lorefalconi@gmail.com

Examples

#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"))

Results

R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> library(SDMTools)
> png(filename="/home/ddbj/snapshot/RGM3/R_CC/result/SDMTools/legend.gradient.Rd_%03d_medium.png", width=480, height=480)
> ### Name: legend.gradient
> ### Title: Legend Gradient
> ### Aliases: legend.gradient
> 
> ### ** Examples
> 
> #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"))
> 
> 
> 
> 
> 
> dev.off()
null device 
          1 
>