You can use the ggplot2 syntax to add aesthetics and ths map color to categories. Using the corrgram package The corrgram is another great alternative to build correlograms. You can choose what to display in the upper, lower and diagonal part of the figure: scatterplot, pie chart, text,...
correlation matrix. It is very useful to highlight the most correlated variables in a data table. In this plot,correlation coefficientsis colored according to the value.Correlation matrixcan be also reordered according to the degree of association between variables. The Rcorrplotpackage is used here...