Update1: I realize that PDL may be quite well suited for much of the above workflow, but I have had major issues with PDL's image plotting modules. Maybe I can do first part of the work with PDL, but am not very confident about generating images with it.

Update2: Added potential module names to tasks.

I want to visualize numbers in a table as a color ramp (or other color schemes). Below is how I would go about it. I am looking for suggestions for improving the process, and for modules that I can use.

Note: All numbers map to locations, hence, are values (for that particular variable) that can be placed on a rectangular image. In other words, the "rainfall" table has rainfall numbers that I want to convert to an image, one number per pixel.

  1. $res = SELECT rainfall FROM rainfall_table WHERE <condition>. use DBI;
  2. convert $res into an "interval" data set that can be mapped to a color table, otherwise their will be way too many colors, pointless in a web application anyway use Statistics::Descriptive; ??
  3. choose a color scheme, preferably one that can follow good color principles, such as espoused by Cindy Brewer's http://colorbrewer.org. Or, at the least, be able to say -- "make me an image using a color ramp from 'dark blue (some rgb combo)' to 'bright pink (some rgb combo)'" use Imager::Color::Table; ??
  4. generate the image use Imager or Image::Imlib2 or ImageMagick or GD; ??
Of course, the db work need DBI/DBD. But, what would I use to generate statistics on $res above? For example, converting the retrieved rows into interval groupings of different classes? Any suggestions for color table matching? And, what are the suggested modules for generating the image -- CPAN is full of image modules. I have ImageMagick already installed, but there is GD, the old stalwart, Imager, and a whole bunch more. Any toolbox with such tools already built in?
--

when small people start casting long shadows, it is time to go to bed

In reply to visualizing data in a table by punkish

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