topic Re: How to assign areas of raster intersecting with polygons in ArcGIS Spatial Analyst Questions

How to assign areas of raster intersecting with polygons

JamesGrellier — Tue, 04 Dec 2018 15:46:36 GMT

I have a raster data set of land cover and a set of residential addresses (points). It looks something like this:

I want to find out what percentage of each land cover type is within 1km of each address (i.e. in a 1km buffer around each point).

Were the land cover also a polygon, it would be no problem to use the intersect tool. However, that doesn't work with raster data. My raster data is too large to convert into polygons.

The table I need to output should contain the ID of the buffer and the areas covered by each land cover type within that buffer.

I realise that this may be an extremely basic problem, but I'd very much appreciate any suggestions for appropriate tools I might use. Many thanks in advance.

Re: How to assign areas of raster intersecting with polygons

JakeSkinner — Tue, 04 Dec 2018 16:55:47 GMT

Hi James,

The Zonal Statistics as Table may give you the result you're looking for. However, take note of the following for your Input value raster:

The Input value raster (in_value_raster in Python) can be either integer or floating point. However, when it is floating-point type, the options for calculating majority, median, minority, and variety will not be available.

Re: How to assign areas of raster intersecting with polygons

DanPatterson_Retired — Tue, 04 Dec 2018 17:00:20 GMT

you could convert your buffers to a raster using the same cell size, extent and snap raster, then examine the results of

Combine—Help | ArcGIS Desktop

This would work best if you treated the buffers as a single unit, ie they were reclassed to a single value... buffer (ie 1) non-buffer ( nodata)