7
votes
Set raster values to a specific number
Use Raster Calculator with an if-condition, available since QGIS 3.22, with this expression:
if ("raster@1" >= 5 , 5, "raster@1")
- 54.7k
6
votes
Accepted
Generating new raster by combining the values of two separate ones in Python
You can use this script.
import rasterio
import numpy as np
# CHANGE paths
file1 = r"c:\path\to\raster1.tif"
file2 = r"c:\path\to\raster2.tif"
output = r"c:\path\to\outout....
- 68.8k
5
votes
Accepted
Set raster values to a specific number
One tool you can use in QGIS is Reclassify by Table.
Your table should look like this:
- 611
4
votes
NoData masks in QGIS
Run Raster Calculator with an expression like raster@1 >= 0 or raster@1 <=0 - this will produce on output with all not empty pixels set to 1
Run Menu Processing > Toolbox > Fill NoData ...
- 54.7k
4
votes
Accepted
NoData masks in QGIS
First, you need to know what value is assigned to the nodata tag. You can see it in the Information tab of the layer properties:
The pixels currently have that value (-1.25 in my case). I assume in ...
- 13.1k
3
votes
Inverting values of raster file using QGIS
Invert values with QGIS Raster Calculator:
-1 * "yourRaster@1" + MAX("yourRaster@1")
but MAX() is not working properly according to some QGIS Bugs Reports.
Instead of MAX() put ...
- 475
2
votes
Accepted
Sum two rasters to combine a building height raster and DTM
I supposed that the buildings raster has a lot of NULL value. You first need to convert null value to 0. Then in raster calculator:
IF(buildings@1>0, buildings@1+DTM@1, DTM@1)
Be careful, if you ...
- 1,284
2
votes
Sum two rasters to combine a building height raster and DTM
Without seeing your data nor your outputs I would suspect that the elevation values in your build heights raster have no data values between the building footprints. Unless otherwise declared, a ...
- 8,412
1
vote
Accepted
Use a conditional raster calculator formula with exponential from ArcGIS in QGIS
The following works:
(("P@1" - "ETP@1" < 0)*"RUx@1" *("P@1" - "ETP@1") / "RUx@1" ^2.71828)+( "RUx@1"+"P@1"-"ETP@...
- 423
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