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PolyGeo ♦
PolyGeo ♦
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How can Ito center a continuous raster layer by subtracting the mean and dividing by the standard deviation using qgisQGIS raster calculator?

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I'm trying to extrapolate a spatial model to a map in QGIS using the raster calculator. The model predicts the value of a pixel given the environmental conditions at this location (e.g. elevation, slope, ect.). Hence, each explanatory variable is a raster layer. For the model I centered my covariates by subtracting the mean and dividing by the standard deviation. Now I want to do the same to my raster layers. As trivial as this seems, I didn't manage to do so. I tried (among similar attempts - like changing upper case, etc.):

(my.raster-mean(my.raster))/sd(my.raster)

The calculator tells me the expression is valid, however, mean() and sd() don't work. 

And I could not find a site with the built-in functions for the raster calculator. Any help in this is most apreciated! Many thanks in advance!

How can I center a continuous raster layer by subtracting the mean and dividing by the standard deviation using qgis raster calculator?

0 down vote favorite

I'm trying to extrapolate a spatial model to a map in QGIS using the raster calculator. The model predicts the value of a pixel given the environmental conditions at this location (e.g. elevation, slope, ect.). Hence, each explanatory variable is a raster layer. For the model I centered my covariates by subtracting the mean and dividing by the standard deviation. Now I want to do the same to my raster layers. As trivial as this seems, I didn't manage to do so. I tried (among similar attempts - like changing upper case, etc.):

(my.raster-mean(my.raster))/sd(my.raster)

The calculator tells me the expression is valid, however, mean() and sd() don't work. And I could not find a site with the built-in functions for the raster calculator. Any help in this is most apreciated! Many thanks in advance!

How to center continuous raster layer by subtracting mean and dividing by standard deviation using QGIS raster calculator?

I'm trying to extrapolate a spatial model to a map in QGIS using the raster calculator. The model predicts the value of a pixel given the environmental conditions at this location (e.g. elevation, slope, ect.). Hence, each explanatory variable is a raster layer. For the model I centered my covariates by subtracting the mean and dividing by the standard deviation. Now I want to do the same to my raster layers. As trivial as this seems, I didn't manage to do so. I tried (among similar attempts - like changing upper case, etc.):

(my.raster-mean(my.raster))/sd(my.raster)

The calculator tells me the expression is valid, however, mean() and sd() don't work. 

And I could not find a site with the built-in functions for the raster calculator.

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Benedikt Gehr
Benedikt Gehr
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How can I center a continuous raster layer by subtracting the mean and dividing by the standard deviation using qgis raster calculator?

0 down vote favorite

I'm trying to extrapolate a spatial model to a map in QGIS using the raster calculator. The model predicts the value of a pixel given the environmental conditions at this location (e.g. elevation, slope, ect.). Hence, each explanatory variable is a raster layer. For the model I centered my covariates by subtracting the mean and dividing by the standard deviation. Now I want to do the same to my raster layers. As trivial as this seems, I didn't manage to do so. I tried (among similar attempts - like changing upper case, etc.):

(my.raster-mean(my.raster))/sd(my.raster)

The calculator tells me the expression is valid, however, mean() and sd() don't work. And I could not find a site with the built-in functions for the raster calculator. Any help in this is most apreciated! Many thanks in advance!