ArcGIS Zonal Histogram – Fix Zonal Histogram Fails to Create Output Table When Looping

arcgis-10.0arcgis-10.1pythonpython-2.7raster

Using python I'm having problems when trying to attempt a FOR LOOP with the ZonalHistogram function of ArcGIS 10.1. It works fine if I use it only for one image but it gives me this error while for looping:

ExecuteError: ERROR 999999: Error executing function.
Create output table failed
Failed to execute (ZonalHistogram)

Here is my very simple script:

import arcpy
from arcpy.sa import *

arcpy.env.workspace = 'G:\\Chile_2012\\MODIS10A2.V005\\prova'

elev_ranges = 'G:\\Chile_2012\\MODIS10A2.V005\\DEM\\elev_ranges'
list = arcpy.ListRasters ()
out_dir = 'G:\\Chile_2012\\MODIS10A2.V005\\prova\\hypso\\'

arcpy.CheckOutExtension ('Spatial')

for raster in list:
    ZonalHistogram (raster, 'Value', elev_ranges, out_dir+ raster+ '.dbf')

Best Answer

Solved.

The problem was assigning a name to the output table (as specified in the "SP5 announcement" of ESRI). I created "in_memory" files by appending an 'in_memory' string at the end of the pathname, and made a list on the temporary tables created in this way to merge them with the "Merge" tool. Tyhen I deleted all the temporary files by using the "arcpy.Delete_management ('in_memory')" tool and it worked fine. Hope this could help someone in the future. Here is the link with some bugs of ESRI. http://downloads2.esri.com/support/downloads/other_/185410.0_SP5_Announcement.pdf

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[GIS] Python loop Polygon to raster not working

The problem is that your code defines raster_outputpath but you try to save the raster in raster_output.

Change this line:

arcpy.PolygonToRaster_conversion(featureClass, "CLASS", raster_output, "CELL_CENTER", "NONE", "30")

To:

arcpy.PolygonToRaster_conversion(featureClass, "CLASS", raster_outputpath, "CELL_CENTER", "NONE", "30")

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