topic Re: Automatically summarize area of polygons within polygon in Geoprocessing Questions

Automatically summarize area of polygons within polygon

PV — Fri, 28 Mar 2014 09:24:49 GMT

I read similair questions but I couldnt figure out the answer yet..

What I have:
-A fire polygon set with information about each year and the area
-A second polygon set consisting of a lot of small polygons

I did an identity overlay to get the fires per small polygon. Then I created new layers for each year. Now I have the fire polygons
for all years needed per small polygon

What I want:
I need to calculate the area of the fires for every small polygon (per year).

I know how to do this manually (select all fires in small polygon and go to summarize area) but since I have a lot of small polygons I need to do this automatically. Any suggestions on how to do this?
I read about the Geospatial Environment Model option (but I cannot make it work) and about the Hawths Analysis tool which unfortunately is not available for ArcGIS10 anymore.

Thanks for the help and suggestions!!

Re: Automatically summarize area of polygons within polygon

markdenil — Fri, 28 Mar 2014 12:30:55 GMT

If I am following you correctly, I would suggest
looping through the large polygons
using each to do a spatial selection on the smaller polys

make a feature layer from the selection
and summarize the areas in the layer

Re: Automatically summarize area of polygons within polygon

PV — Fri, 28 Mar 2014 14:24:36 GMT

thank you.. I think you got my question correctly, but can you explain me a bit more in detail how this works?
which tool do I use to loop through all the polygons? and how can you automatically select the polygons within the polygon?
and is it possible to save the summarized area in a table, with information to which mother polygon it belongs too?

Maybe I started off wrong from the beginning. Let me explain in more detail. My goal is to calculate the fractions of the red polygons (see screenshotI)
per raster cell. (screenshot shows only a small part of the whole dataset). Therefore I need to know the area for all red polygons per
cellpolygon.
I performed "raster to polygon" and got a lot of single polygons (beige squares) with GRIDCODE (attribute table). The former
raster cells (which are polygons now) can contain several different fire polygons for which the area per cell must be calculated.
I desire a table with cellpolygon ID (GRIDCODE) and the summarized area burned per cellpolygon.