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<p class="MsoNormal">It appears that there are two different native raster calculator tools in QGIS<o:p></o:p></p>
<p class="MsoNormal">One is found in at the top of the raster menu<o:p></o:p></p>
<p class="MsoNormal">The other is in the processing toolbox in the raster analysis group<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">(Not to mention the GDAL raster calculator and SAGA raster calculator)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Can anyone explain the reason for there being two, and what the differences are?<o:p></o:p></p>
<p class="MsoNormal">I’ve been very confused by it, mainly because the one in the raster menu does not appear to handle negative values correctly. I’d been wondering why NDVI type expressions with negatives randomly worked or not, and discovered it just depended
on which raster calculator I used.<o:p></o:p></p>
<p class="MsoNormal">Is it expected that the one in the raster menu doesn’t handle negative values correctly? It looks like it might do calculations based on unsigned integers regardless of the input and output raster formats.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><span style="color:#1F497D;mso-fareast-language:EN-GB">Michael Dufty</span></b><span style="color:#1F497D;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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