Hi, i have a raster file about land usage (crops / urban areas ecc…)
I have defined some zones around some given points of a vector layer and I’d like to calculate the % of those areas occupied by each value of the raster file in order to make an estimate on the average usages of the selected areas.
I know that in arcgis there is a function to do so called “Tabulate Areas”, but I can’t find such feature in GRASS.
If anyone can help me I’d be so grateful.
Regards,
–
Alejandro Coca Castro
Hi, i have a raster file about land usage (crops / urban areas ecc…)
I have defined some zones around some given points of a vector layer and I’d like to calculate the % of those areas occupied by each value of the raster file in order to make an estimate on the average usages of the selected areas.
I know that in arcgis there is a function to do so called “Tabulate Areas”, but I can’t find such feature in GRASS.
I think you can use r.stats for this. First rasterize your (vector) areas with v.to.rast. Use a numeric column for the “use=attr” option. Then use r.stats with both the landuse raster and the zones raster as input.
So if you have a “landuse” raster, and a “zones” vector with i.e. a “zone_id” column, then:
v.to.rast in=zones out=zones use=attr colu=zone_id
r.stats -p in=zones,landuse fs=, out=landuse_zones_percent.csv