I'm trying to create a heatmap on a shapefile of numerous points based on a single field in their attribute table.
The header of the attribute table is this:
... and I want to make a heatmap weighted on the "frp" field from the attribute table. However, in the Heatmap (Kernel Density Estimation) settings, I cannot see the "frp" field - only the "longitude" and "latitude" values appear:
What could be wrong here?

