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What is raster calculator in qgis?
The Raster Calculator in the Raster menu allows you to perform calculations on the basis of existing raster pixel values (see figure_raster_10). The results are written to a new raster layer with a GDAL-supported format. In the Result layer section, you will need to define an output layer.
How do I delete a raster value in ArcGIS?
Erasing or filling selected cells
- Click the Raster Cleanup menu on the ArcScan toolbar and click Start Cleanup.
- Click Erase Selected Cells to erase the cells or Fill Selected Cells to paint over the selected cells with the foreground color.
How to replace no data values in a raster?
The following Raster Calculator expression uses a conditional statement and focal statistics to replace no data values within a raster with a value statistically derived from neighboring cell values.
Can a raster calculator be used in QGIS?
As gene mentions, the raster calculator can also be used to solve this in QGIS. Note there is the one that comes with QGIS as well as one (RasterCalc) or more plugins available that may have different capablities. There are several ways you could approach the problem with different formulas (such as a conditional statement or diff function).
How to redefine nodata value into zero in QGIS?
With this calculation, if the cell value is -32768 you will get a 0 in that cell and if it is different from -32768 the cell will keep the value it had. The simplest one-step and, IMO, most consistently reliable solution to reclassifying NoData to zero is to use the Reclassify Grid Values tool (SAGA) in the processing toolbox.
Do you need to add the difference between the two rasters?
As you said in the question, just adding them won’t work since it doesn’t account for the relative difference between top of dam and ground. You need to add the difference between the two rasters to the first raster to effectively replace the values of overlap. You can first get the difference by R3=R2-R1.