# Calculating area of polygon within square mile in ArcGIS?

I would like to create a raster, where in every cell it returns the area of land in a polygon feature. So for example, every cell in the raster would give park land per square mile, or vacant land per square mile.

Edit: I'm having a hard time communicating what I want to do. I have a polygon layer with park land. I want to find, for each unit in a raster grid, the amount of park land within a square mile of each raster cell.

• Can you rephrase your question? What you are trying to accomplish is unclear. – reevesii May 20 '16 at 19:07
• I don't see how this is unclear. I am trying to calculate the amount of land per square mile. I have a polygon feature (that I converted to a raster if necessary), that I want to use as an input. – Steve Scott May 20 '16 at 19:14
• Please use the edit button beneath your question to revise it with this and any additional clarifications. – PolyGeo May 20 '16 at 19:26

## 2 Answers

What you want is probably no raster in the classic way. (in a classic way you would have a band for each land use)

Probably you want to use a polygon-raster, which is a feature class consisting of regular polygons (squares for example with 1 mile size). You can create it with the tool "Create Fishnet". After you have your polygon raster you use intersect on them. You get the polygon parts of each land use for each square. You calculate the area for them and divide them by 1 square mile and you have the percentage. You also have the ID of your polygon-raster through the intersect.

The other possiblity is to use "Polygon to Raster" on your landuse feature. After that you use "Zonal Statistics" (with sum option) with your created polygon-raster. This requires the spatial analyst extension and puts out a raster.

• "The other possiblity is to use "Polygon to Raster" on your landuse feature. After that you use "Zonal Statistics" (with sum option) with your created polygon-raster. This requires the spatial analyst extension and puts out a raster." This is closer. I want to use a raster. But I do not have pre-assigned zones. I want each cell to calculate a the amount of land within a square mile from that cell. – Steve Scott May 20 '16 at 19:57
• But your 1 squaremile features from the polygon-raster are the zones...This way you also get the percantage as the number of cells divided by the number of cells in a square mile. – Matte May 20 '16 at 20:02

Figured it out. Spatial Analyst Tools -> Neighborhood -> Focal Statistics

Edit: The first step is to convert the polygon to a raster layer, and then use Focal Statistics to calculate the sum of the land in a square mile.