I can’t figure out how to do this in QGIS. I tried gdal and SAGA raster calculator in QGIS. Here is the situation: I have two raster for the same area in the same projection with the same extent and the same resolution.
Raster A (has integer values from 1 to 5)
Raster B (has values from 1 to 7)
The calculation should do the following: if a cell in raster B is >= 3, make the cell for raster A + 1. So the result should be the whole raster A, but cell values in raster A where raster B is bigger than 3 should be +1.
My formula so far (for GDAL):
((A*(A>=3))+(B>=3))+(A*(A<3))
But the result is missing all values lower then 3. Anyone any suggestions?
Best Answer
As to the SAGA Raster calculator (
QGIS Processing Toolbox | SAGA | Raster calculus | Raster calculator
).SAGA formula is:
A catch is that
b >= 3
becomesOR(b>3, b=3)
.OR(x,y)
returns true (1), if at least one of both x, y is true.