README REDO (based on proposed structure in Issue cnerg#2): master README updated, directory README added

Author: opotowsky

README.md

@@ -2,7 +2,5 @@
 Scripts, settings and environment options for better research and analysis
 
 ## tri_heatmap: Heatmaps in matplotlib
-This notebook gives some guidance on plotting 2D heatmaps in matplotlib given
-the existence of X, Y, Z experimental data.  This uses triangulation to form a
-triangular grid and then applies tricontourf (or tripcolor) to get the surface
-plot with a colorbar.
+This directory includes a notebook that gives some guidance on plotting 2D
+heatmaps in matplotlib given the existence of X, Y, Z experimental data.  

tri_heatmap/README.md

@@ -0,0 +1,12 @@
+# Heatmaps in matplotlib
+Given X, Y, Z experimental data suited to heatmap plotting, one can follow the
+steps in this notebook to get a surface plot with a colorbar.  This notebook
+shows three varieties of surface plots using toy data.
+
+For all plots, it first uses triangulation on the X, Y data to form a
+triangular grid (and normalizes the colors to the z range).  There are three
+methods used to plot the surface:
+1. tricontourf
+2. tripcolor with flat shading
+3. tripcolor with Gourard shading
+Note that the color bar is only smoothed with tripcolor.