5

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.

Improve this question
2
  • Cell size is used for generating output. You may have a look at docs.qgis.org/2.0/en/docs/user_manual/plugins/…
    – Learner
    Commented Jan 17, 2015 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
    Commented Jan 19, 2015 at 22:47

1 Answer 1

Reset to default
0

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.

Improve this answer

Not the answer you're looking for? Browse other questions tagged or ask your own question.