I have generated a nice heatmap (point density) based on a point layer using the QGIS Heatmap plugin, set up as follows:
I calculated both outputs as shown in the screenshot below:
- 'Scaled by Kernel size' range from 0 ... 0.0212594
- 'Raw values' range from 0 ... 60.1269
... as indicated by the legend. Strangely, identifying on the resulting maps at the coordintes given by the yellow circle (300m Radius, Points within search radius count ~883) gives values far exceeding the max values in the legend:
- 'Scaled by Kernel size' 0.0859
- 'Raw values' 243.2
Isn't the raw value the point count within the search radius (here ~883
) and the scaled value the points per area (here: #points/m²
, ~0.003...
)?
Two questions:
- How to interpret the legend values, what units do they have?
- why am I sampling values so far exceeding the max values in the legend?