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There was already How to build effective heat-maps? from 2010 where the answer was basically "use QGIS Heatmap plugin".

I've also read on QGIS webpage that it is now "implemented as a native C++ plugin"

What is the best way to generate a heatmap from a list of observations, in QGIS?

PolyGeo
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Antonin
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1 Answers1

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I've just learned that the heatmap plugin is not part of version 1.7, so if that's what you're using (like I am), it's not here for us to use it yet. If you're using the "trunk" version of QGIS the heatmap can be found under the Raster menu.

dianamaps
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  • (and I just notice now it was written in the 2010 question: "QGIS Heatmap plugin (available in versions > 1.7.x)", strict >) – Antonin Mar 23 '12 at 14:59
  • I installed QGIS 1.9, and there is a heatmap pluging. I imported 186 points in my map (delimited text layer), and from these points I'm trying to create my heatmap with the plugin. Unfortunately, I only get a grey rectangle. I'm working on a space of order of magnitude of 0.005 degrees, with a buffer radius of 10 and a decay ratio of 0.5. Does anyone have an idea how I should use the plugin? – Antonin Mar 25 '12 at 20:34
  • Hi Antonin. I'm not able to help you with the plugin itself since I can't use it with my Windows 1.7 version yet. But I'm questioning your spatial coordinates themselves. Heat maps (i.e., density maps) should be generated with points that have been projected, away from degrees (spherical coordinates). You'll want to have a regular, Cartesian surface (and probably end up with units in meters or km for your buffers and ratios). Can you project the data first to whatever might be a suitable projection for your AOI? – dianamaps Mar 25 '12 at 22:01