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Does anyone know if there exists in QGIS any tool similar to "Tabulate Area" of ArcGIS to be able to calculate what percentage of values of a raster for each polygon?

So far I am using pktools, pkextract but the time it takes to process is huge, not acceptable for very large surfaces.

Alejandro Chamizo de Castro
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    possible duplicated https://gis.stackexchange.com/questions/23280/is-there-a-tabulate-area-function-in-qgis – Fran Raga Jan 10 '18 at 15:48
  • can you be more explicit as to what you mean by large surfaces (i.e. number of pixels and polygons)? I use pkextract on very large datasets without any trouble. – dmci Jan 10 '18 at 16:10
  • I refer to large raster, for example watersheds. I usually use pkextract to calculate what percentage of soil types there are in several basins of a hydrographic basin. This operation is almost instantaneous using tabulate area in Arcgis but using pkextract can last hours. I'm afraid something should not be doing well – Alejandro Chamizo de Castro Jan 11 '18 at 16:37

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Zonal Histogram (QGIS 3.4) has worked successfully for me to derive land cover totals (from a TIF) per county (held as shapefile).

I was searching for an answer to this exact same question. However, a different question (about an equivalent for Zonal Statistics) was where I found this information. To me, Zonal Histogram seems to be a more direct equivalent to Tabulate Area than to Zonal Statistics, so I am posting it here to make the answer more easily searchable.

It calculates a total, not a percentage as per the original question, but it at least makes a percentage possible to calculate.

ermintrude75
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