topic Re: Area of a raster in Python in Python Questions

Area of a raster in Python

NataliaOcampo — Fri, 09 Nov 2012 01:01:01 GMT

Hello,

I have a file full of rasters with a Value of 1, the rest is NoData.
I need to extract the Count for each raster, to then calculate the area, by multiplying by the cellsize.

I was trying to do this with the Get Raster Properties tool, using UNIQUEVALUECOUNT as the property type yin the script but instead of returning the count, it would return a 1.

count = arcpy.GetRasterProperties_management (fileName, "VALUETYPE")

Is there an automated way to extract the count from a raster, using Python????

I would really appreciate your help.

thanks!

Re: Area of a raster in Python

MarcinGasior — Fri, 09 Nov 2012 05:32:50 GMT

There's no simple property of COUNT for raster values.
It can be read from raster attribute table with a search cursor in this way:

import arcpy,  inRaster = r"C:\test.gdb\myRaster"  # Build attribute table if needed #arcpy.BuildRasterAttributeTable_management(inRaster, "OVERWRITE")  # Create a search cursor for desired raster VALUE sCur = arcpy.SearchCursor(inRaster, '"VALUE" = 1') for row in sCur:     cellCount = row.getValue("COUNT")     print cellCount

Re: Area of a raster in Python

NataliaOcampo — Fri, 09 Nov 2012 12:56:33 GMT

Thank you so much!

This was very helpful!