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I created a few heatmaps with the new plugin in QGIS 1.9, but now I would like to generate a lot of them automatically. How should I do?

I created a few of them by hand, but I should first import the data, select the CRS, then select the plugin, select the imported data and the parameters for the heatmap (and pick again the CRS). It takes quite long as soon as you want more than a few heatmaps.

I have 300'000 data in one day. I separate them in groups of 15 minutes, and I would like to visualize the heatmap for all groups of 15 minutes (~64), in order to observe the evolution in time.

I'm interested in either:

  • a way to make it in QGIS automatically, or
  • a way to do it in another software, that would be more adapted for this purpose.
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The Heatmap is a plugin in the QuantumGIS application and thus doesn't have any API bindings. Hence I am afraid, there would be no way you could generate it through the command line. If your requirement is simply visualization without any spatial analysis, then kindly take a look at https://github.com/sethoscope/heatmap This is the parent project upon which the plugin was created.

  • It works pretty well. The creation of heatmaps is a bit slower, but it has a lot of options. In particular, you can use OpenStreetMap as a background picture, and create an animation of the accumulation of points. – Antonin Apr 4 '12 at 12:20
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Depends on what you do. If your heatmap is result of interpolation of point values you can try using gdal_grid command line tool (http://www.gdal.org/gdal_grid.html). It supports main interpolation algorithms (IDW, NN, etc.). Once you figure out the command that suits you, it is easily scriptable by looping it or by simple repeating as many times as you need feeding it different data and outputing different rasters.

You can run gdal_grid easily if you install QGIS with OSGeo4W installer. It comes with built in shell.

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You should look at this post which had been cited before. How to build effective heat-map

I hope it helps you

  • Thanks for the answer. I read this post before. It's not exactly what I'm looking for. I already made a heatmap, but I'm looking for a way to make a lot of them, to write a script to create them. I could do it by hand as well (I need to do 64 maps, something like this), but imagine I want to change one parameter. Or do it for another data set. It would be really better to use QGIS automatically. – Antonin Apr 1 '12 at 21:19

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