Arcpy "Slope" Function does not work.

MikeMoehlmann — Fri, 17 Nov 2023 11:56:19 GMT

I'm using ArcGIS Pro 3.1.1

I'm encountering an issue when I try to run the "Slope" tool in arcpy. First of all, when I run the tool manually the tool runs without any problems. But in Arcpy, it does not work, even if I use the code from "Send To Python Window" from the manual execution.

Here is my code:

out_raster = arcpy.sa.Slope( in_raster="dtm_mask", output_measurement="DEGREE", z_factor=1, method="PLANAR", z_unit="METER", analysis_target_device="GPU_THEN_CPU" ) out_raster.save(r"C:\Users\Desktop\slope_test")

Resulting in the following error:

Traceback (most recent call last): File "<string>", line 1, in <module> File "C:\Program Files\ArcGIS\Pro\Resources\ArcPy\arcpy\sa\Functions.py", line 8685, in Slope return Wrapper( File "C:\Program Files\ArcGIS\Pro\Resources\ArcPy\arcpy\sa\Utils.py", line 55, in swapper result = wrapper(*args, **kwargs) File "C:\Program Files\ArcGIS\Pro\Resources\ArcPy\arcpy\sa\Functions.py", line 8632, in Wrapper z_meters_per_unit = linear_unit_factors[zlu] KeyError: 'METRE'

So it says that there is a KeyError with "METRE", but I defined in the "z_unit" "METER".
How can I solve this problem? Is there maybe something wrong in the source code of the "slope" function?

Re: Arcpy "Slope" Function does not work.

MikeMoehlmann — Thu, 14 Dec 2023 08:25:44 GMT

I found that the error "KeyError: 'METRE' only appears when using the 'arcpy.sa.Slope()' function from the Spatial Analyst toolbox. When using the slope function from the 3D-Analyst toolbox it works:

try: for raster in arcpy.ListRasters(): if "DTM_mask" in raster: raster_name = raster arcpy.ddd.Slope( in_raster= raster, out_raster=f"{raster}_slope", output_measurement="DEGREE", z_factor=1, method="PLANAR", z_unit="METER", analysis_target_device="GPU_THEN_CPU" ) except Exception as e: print(f'Error: {str(e)}')

Still, when I use the function manually, no matter from the Spatial Analyst or 3D-Analyst toolbox it works without any problems. Also the documentation specifies a 'Slope()' function, which seems to does not even exist (I'm using ArcGIS Pro 3.1.1):

Error: name 'Slope' is not defined

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Arcpy "Slope" Function does not work.

Re: Arcpy "Slope" Function does not work.