How to set up 'Extent' environment variable with arcpy when using CellStatistics?

Question

I have a set of rasters of different extent and I have written a script to combine them all into one raster using CellStatistics:

import arcpy
from arcpy.sa import *

arcpy.env.workspace = r'C:\ESRI\ArcGIS_Pro_Projects\DATA\Optimity_Alf\Work.gdb'

#Path where rasters are located
path = r'C:/ESRI/ArcGIS_Pro_Projects/Optimity_Alf/DATA/Work.gdb'

#List of raster names from workspace
rasters = arcpy.ListRasters('*', 'All')

#Building list of raster complete paths
paths = []
for raster in rasters:
    if raster[0] != '_':
        complete_path = path + "/" + raster
        paths.append(complete_path)

#Combining rasters into one unique raster
path_combined_raster = r'C:\ESRI\ArcGIS_Pro_Projects\Optimity_Alf\DATA\Work.gdb\Combined_Raster'
combined_raster = CellStatistics (paths, 'MINIMUM', 'DATA')
combined_raster.save(path_combined_raster)

However, when I run this script it throws the following error:

    Traceback (most recent call last):
  File "C:\ESRI\ArcGIS_Pro_Projects\Optimity_Alf\Arcpy_Scripts\Combining_Viewsheds.py", line 21, in <module>
    combined_raster = CellStatistics (paths, 'MINIMUM', 'DATA')
  File "c:\program files\arcgis\pro\Resources\arcpy\arcpy\sa\Functions.py", line 3173, in CellStatistics
    ignore_nodata)
  File "c:\program files\arcgis\pro\Resources\arcpy\arcpy\sa\Utils.py", line 53, in swapper
    result = wrapper(*args, **kwargs)
  File "c:\program files\arcgis\pro\Resources\arcpy\arcpy\sa\Functions.py", line 3169, in Wrapper
    [function] + Utils.flattenLists(in_rasters_or_constants))
RuntimeError:  ERROR 999998: Unexpected Error.
 Failed to execute (CombinedViewsheds).

I have no idea what all that error message means. However, I tried to do the same operation in ArcGIS Pro and got an error regarding the extent of the rasters. Therefore I went to Environments and set the extent to 'Union of Inputs'. That change made the thing work fine. My question is, how can I set the extent in arcpy? The instruction "CellStatistics (paths, 'MINIMUM', 'DATA')" does not accept more parameters.

Answer 1

You can set the extent using the env module, prior to running Cell Statistics:

arcpy.env.extent = "MAXOF"

See here for the scripting syntax of the extent variable.