I have a process in which I need to use coverages. I can create the coverages just fine using FeatureClassToCoverage_conversion within arcpy but trying to union 2 coverages together does not work in arcpy with the identified method "Union_arc". I suspect it has something to do with creating an ArcINFO workspace, but I do not know how to use this for _arc commands.

The error is "Object: Tool or environment not found" I have ArcINFO installed and can run these tools successfully in Modelbuilder. I have attached a test script to get Union working. Running 10.1 ArcGIS python 2.7.

import arcpy, os, sys
from arcpy import env
print 'Starting....'
env.OverWriteOutput = True

env.workspace = "G:\\Projects\\P747\\3_Landbase\\LB1\\temp\\test2\\"
TEMP = "\\\\silver\\clients\\Projects\\P747\\3_Landbase\\LB1\\TEMP\\"

print 'Loaded Data....'
if arcpy.Exists(TEMP + "airworkspace3"):
    arcpy.Delete_management(TEMP + "airworkspace3")
arcpy.CreateArcInfoWorkspace_management(TEMP, "airworkspace3")

r = str(1)
for fc in arcpy.ListFeatureClasses():
    print 'Working on ' + fc

    CovName = TEMP + "airworkspace3\\" + "Layer1"
    CovName3 = TEMP + "airworkspace3\\" + "Success"

    if arcpy.Exists(CovName + str(r)):
        arcpy.Delete_management(CovName + str(r))

    arcpy.FeatureclassToCoverage_conversion(fc + " POLYGON", CovName + r, "", "DOUBLE")
    r += str(1)

print 'Working on Union'    
arcpy.Union_arc(CovName + "1", CovName2+ "2", CovName3)

print 'Completed ' + fc + ' processing....'   
  • what is the error message?
    – mwil
    Commented Jan 16, 2015 at 21:23
  • can you run the tools and then use Geoprocessing>Results>CopyAsPythonSnippet to help with the code?
    – mwil
    Commented Jan 16, 2015 at 21:24
  • That is what I have done and the tools are not recognized by arcpy
    – D_C
    Commented Jan 16, 2015 at 21:30
  • stand alone or in the python window?
    – mwil
    Commented Jan 16, 2015 at 21:33
  • 1
    Would you be able to edit your question to include a code snippet that can be used by someone with an Advanced level license to see precisely where you are stuck, please?
    – PolyGeo
    Commented Jan 17, 2015 at 2:50

1 Answer 1


After much fanfare, I found this to work. Seems really strange to have to re-name an alias, but it worked.

import arcinfo, arcpy, os, sys
from arcpy import env

tbx = arcpy.ImportToolbox(r"C:\Program Files (x86)\ArcGIS\Desktop10.1\ArcToolbox\Toolboxes\Coverage Tools.tbx", "newalias")

print arcpy.Usage("union_newalias")

arcpy.Union_newalias(CovName1, CovName2, CovName3)

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