In this post, we will see how can we add text annotation to heatmaps made with ggplot2. In ggplot2, we can make simple heatmaps using ggplot2's geom_raster() and geom_tile(). In this post, we will use geom_text() to add text annotation, i.e. numerical values in the heatmap. We … [Read more...] about How to add text annotation to heatmap with ggplot2