actually making heatmaps is rather easy, checkout: <a href="http:&#x2F;&#x2F;docs.ggplot2.org&#x2F;current&#x2F;geom_tile.html" rel="nofollow">http:&#x2F;&#x2F;docs.ggplot2.org&#x2F;current&#x2F;geom_tile.html</a>