topic Re: Statistics in Geoprocessing Questions

Statistics

jaykapalczynski — Wed, 25 Mar 2015 20:55:18 GMT

I have a polygon layer with a bunch of polygons.

I have a raster Land Cover with a bunch of land cover types.

I want to process the data and come up with statistics of how much of each land cover type is in each of the polygons.

No idea where to start. Is there a tool that can help?

Hope I explained well enough. Thanks

Re: Statistics

jaykapalczynski — Wed, 25 Mar 2015 20:56:19 GMT

Oh and the raster is clipped to all the Polygons.

Re: Statistics

DarrenWiens2 — Wed, 25 Mar 2015 20:57:23 GMT

Zonal Statistics as Table should do this for you.

Re: Statistics

jaykapalczynski — Wed, 25 Mar 2015 21:11:47 GMT

I ran that and its not really what I was going for....

The raster data has a bunch of different land cover types. I was hoping for an output for each polygon with percentages for each of the land cover types ....or total counts of Raster cells for each type I can then calculate % of each type.

Polygon

Land Cover type 1 12%

Land Cover type 2 22%

Land Cover type 3 15%

Land Cover type 4 32%

Re: Statistics

DarrenWiens2 — Wed, 25 Mar 2015 21:22:34 GMT

Oh, you may want to check Tabulate Area. With both of these, if you have overlapping polygons, you will have to process zone features individually, since the zones are converted to raster (flattened), internally.

Re: Statistics

JayantaPoddar — Thu, 26 Mar 2015 12:34:50 GMT

Hi,

Apart from Darren Wiens's suggestion, you could follow another workaround.

1) Convert the LandCover Raster to polygon.

2) Use tabulate intersection to get the area in percentage.

Hope it helps!!!

Re: Statistics

jaykapalczynski — Thu, 26 Mar 2015 13:21:00 GMT

Jayanta...thanks

The big question is would this work with overlapping polygons?

Re: Statistics

JayantaPoddar — Thu, 26 Mar 2015 13:31:35 GMT

The area % would be calculated for each feature irrespective of the overlapping extent.