[GIS] combine two heat-maps in QGIS

Question

I have two heat-maps and related point data layers, one of correspondent sender addresses, the other of recipient addresses. I wish to identify clusters — hotspots — of sender and receiver addresses.

In QGIS, can I create a heat-map from the two point layers to show densities (the Heat-map Plugin only accepts one vector input layer)? Or can I combine the two heat-map rasters to show the coincidences of data?

(QGIS 2.12+)

Answer 1

Knightshound's answer is correct. Another option, if you don't want to create yet another file and keep ti always updated, is to use Virtual Layers. I'm not sure if Virtual Layers is available in QGIS 2.12 though.

• Click add Virtual Layer button

• Enter the following SQL query

select geometry from senders
union all
select geometry from receivers

• Click OK

Now you will have a brand new layer called virtual_layer, that you can use to create the joined heatmap.

Note that the virtual layer will be updated once any of the to layer are edited. Which is nice.