QGIS syntax raster calculator

Question

I'm working with QGIS and I want to reclassify a raster in different ranges.

Using the following statement does not work even recognized as valid

(2950 <= "dem_tallat @ 1"> = 3050) = 3000

Where I can find a document that shows the syntax to use for Raster Calculator?

try this one (2950 <= "dem_tallat@1" <= 3050) = 3000 - you obviously used wrong comparison sign — SS_Rebelious, Oct 21, 2014 at 15:16

Joseph · Accepted Answer · 2014-10-21 14:49:44Z

4

There are a number of sources with examples showing what syntax can be used for rasters. Basically, common mathematical logics are used such as:

Here you can find how some of those syntax are used in some examples.

Other sources can be found in the QGIS documentation:

answered Oct 21, 2014 at 14:49

Joseph

75k7 gold badges167 silver badges279 bronze badges

Ok, thanks. But I don't find any expression to satisfy my purpose. To recognise a range of values and transform this in another value
– narmarant
Oct 21, 2014 at 15:14
Have you tried what @SS_Rebelious suggested?
– Joseph
Oct 23, 2014 at 11:46
Yes, but doesn't works...
– narmarant
Oct 23, 2014 at 15:38

Add a comment |

GISHuman · Accepted Answer · 2017-03-31 17:50:31Z

1

To map values from (2950-3050) into 3000 and preserving other values of dem_tallat :

(2950 <= "dem_tallat@1" AND  "dem_tallat@1" <= 3050)*3000 + (2950 > "dem_tallat@1" OR  "dem_tallat@1" > 3050)*"dem_tallat@1"

GISHuman

3,6611 gold badge20 silver badges41 bronze badges

answered Mar 31, 2017 at 16:45

natan

1265 bronze badges

Add a comment |

2 Answers 2