2

Using ArcMap 10.3, I am trying to perform map algebra on a raster with 2013 annual PRISM precipitation for the U.S. (http://prism.oregonstate.edu/recent/). The raster has 1 band an is floating point.

Using Spatial Analyst Tools > Map Algebra > Raster Calculator (i.e. not within model builder), I have tried to create a new raster by executing these expressions (separately):

"PRISM_ppt_stable_4kmM3_2013_asc.asc" * 0.1 and Float("PRISM_ppt_stable_4kmM3_2013_asc.asc" * 0.1)

Both expressions yield this error:

Raster(r"PRISM_ppt_stable_4kmM3_2013_asc.asc") * 0.1
ERROR 000539: Error running expression: rcexec() 
Traceback (most recent call last):
  File "<expression>", line 1, in <module>
  File "<string>", line 5, in rcexec
  File "c:\program files\arcgis\desktop10.3\arcpy\arcpy\sa\Functions.py", line 4333, in Times
    in_raster_or_constant2)
  File "c:\program files\arcgis\desktop10.3\arcpy\arcpy\sa\Utils.py", line 53, in swapper
    result = wrapper(*args, **kwargs)
  File "c:\program files\arcgis\desktop10.3\arcpy\arcpy\sa\Functions.py", line 4330, in Wrapper
    ["Times", in_raster_or_constant1, in_raster_or_constant2])
RuntimeError: ERROR 999998: Unexpected Error.

Failed to execute (RasterCalculator).

What am I missing here?

  • 2
    Use ASCII to raster tool first – FelixIP Apr 11 '16 at 22:23
  • I agree with @FelixIP ASCII is a text file format and not what I would consider a true raster format, it's more of an "interchange" format that can be read by many software. So you need to convert it first then run your raster calculations. – Hornbydd Apr 11 '16 at 23:00
1

After much trial and error, I discovered there was an issue with my environment settings. Raster outputs were not set to have the same coordinate system as inputs. After I changed that, the raster calculator expressions worked fine.

  • Don't forget to accept your answer by clicking the green tick. – user35594 Jun 10 '17 at 19:46

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.