topic Re: Unique values in raster table in Python Questions

Unique values in raster table

NareshPai — Fri, 30 Mar 2012 18:05:17 GMT

Is there a direct way to store all the unique values in raster attribute table? Right now, I am using a search cursor for attribute table and then, a for-loop to store the values. I wish GetRasterProperties_management would have "UNIQUEVALUES" in addition to the "UNIQUEVALUECOUNT"

Thanks,
Naresh

Re: Unique values in raster table

Zeke — Fri, 30 Mar 2012 19:31:58 GMT

I don't work much with rasters, so maybe this wouldn't work or ArcGIS doesn't support it, but can you run a selection like a "Select Distinct Value..." to get unique values? If so, you could then export them into a table.
Sorry if I'm off base here, I'm thinking in SQL, maybe this is not even on the horizon with rasters.

Re: Unique values in raster table

DarrenWiens2 — Fri, 30 Mar 2012 19:44:59 GMT

I assume you mean "store the individual values" (one row for each pixel)...? Raster attribute tables are a list of unique values.

Re: Unique values in raster table

NareshPai — Fri, 30 Mar 2012 19:52:12 GMT

Hi Darren, Thanks for your response.

Yes, I would like to store all the values in the "Value" field of the table in a variable for categorical raster. The way I do it right now is,

k=0
rows = arcpy.SearchCursor(RasterName,"","","Value","")
for row in rows:
val = row.getValue("Value")
k = k + 1

Can this code be reduced?

Naresh