Possible Duplicate:
Parametrize shading in table through TikZ
Drawing heatmaps using TikZ
I know this isn't strictly speaking a LaTeX question, so please move this somewhere else if you feel like it.
I find large tables of numeric values a bit hard to comprehend at a glance ... or even many. One strategy to alleviate this is to set the hue of the background color according to the value in that cell. So for values in [0, 1], 0 would be red, 0.3 might be yellow, 1 is blue etc.
Has anyone a workflow using open source tools that produces a native LaTeX table (not a picture with strange fonts or suchlike) from a CSV file (or some other format that you can easily convert to with say LibreOffice or gnumeric)?
Choosing a color from a simple gradient would be ok, too, I guess, since then you don't need some HSV→RGB conversion. Examples for this latter variant could look like this (the second isn't with numbers though, obviously):
