library(gplots)

r.cor <- cor(r)

layout(matrix(c(1,1,1,1,1,1,1,1,2,2), 5, 2, byrow = TRUE))

par(oma=c(5,7,1,1))

cx <- rev(colorpanel(25,"yellow","black","blue"))

leg <- seq(min(r.cor,na.rm=T),max(r.cor,na.rm=T),length=10)

image(r.cor,main="Correlation plot Normal/Tumor data",axes=F,col=cx)

axis(1, at=seq(0,1,length=ncol(r.cor)), labels=dimnames(r.cor)[[2]],

cex.axis=0.9,las=2)

axis(2,at=seq(0,1,length=ncol(r.cor)), labels=dimnames(r.cor)[[2]],

cex.axis=0.9,las=2)

image(as.matrix(leg),col=cx,axes=T)