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I am looking for the right formula for reclassifying a slope raster. I need to switch the values 1 = bad, 10 = good to 1 = good, 10 = bad. This Formula worked fine using the normal raster calculator: 10 - %"Recoded@1"% + 1 but I can't figure out the right formula using the SAGA or Gdal Raster Calculator for my processing model. Any ideas!?

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    Do you need to switch just the values 1 and 10, or is it a continuous raster with value ranges between 1 and 10? – HDunn Apr 24 '17 at 18:28
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A direct answer using SAGA Raster Calculator, would be 11- g1 (same as 10 - g1 + 1).

Alternatively, SAGA | Raster tools Invert grid does the same job.

If we test with this example (sorry... I forgot to input 1... and ended up with 10 - g1 + 2).

enter image description here


Since OP's equation had been successful with QGIS raster calculator, I will not worry too much about continuous data. If input was continuous data (e.g. 1.23 - 10.00), the output gets funny and easily recognized.

enter image description here

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Try using the SAGA Tool "Reclassify values". Here you can easily replace one value with another one (for example 1 with 10). Depending on your data, you might have to repeat the process several times to achieve the desired format

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