Useful data visualization of a correlation matrix, code from the R Graphics Cookbook by Winston Chang

corrviz.R

# Function takes a correlation matrix from the cor() function and outputs a visualization.
# The corrplot package must be installed.
# This code comes from the R Graphics Cookbook by Winston Chang

corrviz <- function(mycorrmatrix){
  col <- colorRampPalette(c("#BB4444", "#EE9988", "#FFFFFF", "#77AADD", "#4477AA"))
  corrplot::corrplot(mycorrmatrix, method="shade", shade.col=NA, tl.col="black", tl.srt=45, col=col(200), addCoef.col="black")
}