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I have two layers. The first one is a vector layer with 6 polygons. The other one is a raster layer. I need to extract specific surface information for my polygons (average slope value). The information is available in my raster layer « Alma-ShipshawPente ». Raster to Vector

I want to clip my raster image so it fits the extent of my vector layer and is split by individual polygon features. How should I proceed?

I looked at a few tutorials to help me through. All of them included programming. I am not familiar with programming and, therefore, I have not succeeded yet. Are there other ways to proceed ?

I tried the option Raster > Extraction > Clipper. Here's the result. Clipping test

It is a beginning, but the raster is not split by polygon features. It is clipped according to the extent of the entire layer.

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    You mean something like Raster > Extraction > Clipper and using the vector layer as the mask layer? If so then this post may be considered a duplicate =). How to clip a raster with vector boundaries? – Joseph Mar 1 '16 at 16:14
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    Seems to be clipping the extent of the vector layer instead of the actual polygons. Have you tried using it from the Processing Toolbox > GDAL/OGR > [GDAL] Extraction > Clip raster by mask layer? – Joseph Mar 1 '16 at 16:27
  • @Joseph, i have a french version. I am not able to find the " Processing Toolbox > GDAL/OGR > [GDAL] Extraction > Clip raster by mask layer ". Where is the processing toolbox ? – Laurent Robitaille-Lainesse Mar 1 '16 at 16:40
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    By looking at your image it seems like raster is clipped by the polygons. If the black area is filled with NoData you should have no problem with further analysis. – user30184 Mar 1 '16 at 21:48
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    I believe @user30184 is correct in that the NoData values should not affect the rest of your analysis. The Processing Toolbox can be accessed from the toolbar: Traitement > Boîte à Outils. A panel should open on the right-hand side of the interface (Boîte à Outils de traitements). Then you can just type in the Rechercher box: "découper un raster selon une couche de masque". – Joseph Mar 2 '16 at 10:17
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It seems like what you want to do is clip the raster slope layer to the extent of your entire polygon layer and then split the raster by individual polygons. If so, the GridSplitter plugin should do exactly what you want if you use your clipped raster layer as the input. Just select the "cut layer" option and split by your polygon features.

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