For this model it is not necessary to have the inputs in a 1-100 range, you can use 0-1 and then multiply the output by 100 to get the desired data range for the index. If you are using ArcGIS this toolbox has a tool for statistical transformations, including normalization. It is not intended for use in scripting and is not available in the ArcPy Spatial Analyst module. The reason for this transformation is because the index needs the summed variables to be in the same variable space. Note: The Raster Calculator tool is intended for use in the application only as a GP tool dialog box or in ModelBuilder. In your case you could just normalize and multiply by 100. I don't know how to address that issue currently. I am pretty confident that I created my raster layer correctly and have been told by a few sources that its possibly my Python that is the problem. with the output being: C:\GISEXERCISES\paraster. I provide this example because it allows a specification of any desired output min/max raster values. My raster calculator function is extremely simple: 'bndraster2' + 'trackraster'. Numeric (Double and Long) Data (Raster dataset, raster layer, raster band. The problematic part of the formula that is responsible for the NoData. However, it results in NoData values for some of the pixels. I would like to compute the expression displayed in the image with the Raster Calculator tool by using the slope (degrees) derived from the SRTM 30m DEM data. Numerical values and mathematical operators can be added to the expression by clicking the respective buttons in the tool dialog box. Raster Calculator results in NoData values, ArcMap. Use the Layers and variables list to select the datasets and variables to use in the expression. The min("raster") and max("raster") refer to the global min/max values of the rasters. The Raster Calculator tool allows you to create and execute a Map Algebra expression that will output a raster. The "+ 0" is, in this case, obviously irrelevant but is left in for cases where the desired minimum value is not zero. Here is the raster algebra syntax for a data stretch. The Raster Calculator tool allows you to create and execute a Map Algebra expression that will output a raster. You are wanting a stretch or normalization. Whereas, normalization transforms your data so that the minimum value is 0 and the maximum is 1 while keeping the shape of the original distribution. Standardization refers to transforming your data so it has a mean of 0 and a standard deviation of 1 and is only appropriate for normally (Gaussian) distributed data. The language of data transformation can be confusing.
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