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I am mapping 5 heritage sites using DGPS point data. Each site has 100s, and in two cases 1000s, of points representing various attributes. I want to show the density of attributes and then demonstrate a threshold (no. of attributes) in hot spots for each heritage site.

I have no problems creating heat and hot spot maps following the QGIS instruction manual and Ujaval Gandhi’s tutorials, but I am uncertain about how to use the advanced raster heatmap plugin settings to set the x and y cell size, kernel shape etc. I seem to get different results every time I create a map. So, is it ok to leave the advanced settings off? and just choose the radius? I set the radius to 10m, 5m and 1m depending on the attribute I want to display.

I need the heat mapping to be representative and the hot spot mapping to be accurate.

closed as unclear what you're asking by underdark Apr 30 '15 at 18:32

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • Cell size is used for generating output. You may have a look at docs.qgis.org/2.0/en/docs/user_manual/plugins/… – SIslam Jan 17 '15 at 10:27
  • ad: Is it ok to leave the advanced settings off? - This can only be answered if we really understand your requirements. So far, I would assume that you want a heatmap raster which - for each cell - shows the absolute number of points within a certain radius. Is that correct? Maybe add a small sketch. – underdark Jan 19 '15 at 22:47
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If I understood your question correctly, What you need is a proximity analysis that counts the number of features of a given type per raster cell. If this is what you want you could try GRASS modules (ou can use it from within QGIS) r.distance or maybe r.neighbors.

Anyway this is just a guess - it's not clear at all what you want.

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