Access attribute table of in-memory raster

Question

I'd like to read from the attribute table of an intermediate raster generated by arcpy.sa.Combine:

combined = arcpy.sa.Combine(['raster1', 'raster2'])
arcpy.BuildRasterAttributeTable_management(combined)
data = [row for row in arcpy.da.SearchCursor(combined, ["VALUE", "COUNT"])]

The above code raises: RuntimeError: 'in_table' is not a table or a featureclass

Is there a way to access the RAT without saving the raster?

• FelixIP: Try to create raster layer from it.

Answer 1

Try setting arcpy.env.workspace = 'in_memory', or the cursor will not know where to find the raster.

It could also be that combined is a raster object which the cursor cannot read. Try "saving" it to in_memory workspace:

combined.save(r"in_memory\outcombine2")
data = [row for row in arcpy.da.SearchCursor(r"in_memory\outcombine2", ["VALUE", "COUNT"])]

• Cowirrie: The second solution worked for me: I had to call .save() on the raster and then I could use SearchCursor on it like any other table. This is odd, because you can print the variable containing the output of your raster tool (in your example, you could use arcpy.AddMessage(f"Output raster={combined}") and it too will be a path to a raster. But you can't read its contents as a table. In my case I was using arcpy.sa.ExtractByAttributes, so a lot of raster tools probably do this.