CheckOutExtension

Summary

Retrieves the license from the License Manager.

Once the extension license has been retrieved by the script, tools using that extension can be used. Once a script is finished with an extension's tools, the CheckInExtension function should be used to return the license to the License Manager so other applications can use it. All checked-out extension licenses and set product licenses are returned to the License Manager when a script completes.

Discussion

Tip:

The setting of the product and extensions is only necessary within stand-alone scripts. If you are running tools from the Python window or using script tools, the product is already set from within the application, and the active extensions are based on the Extensions dialog box.

Syntax

CheckOutExtension (extension_code)

Parameter	Explanation	Data Type
extension_code	Keyword for the extension product that is being checked. 3D —3D Analyst Schematics —ArcGIS Schematics ArcScan —ArcScan Business —Business Analyst DataInteroperability —Data Interoperability GeoStats —Geostatistical Analyst JTX — Workflow Manager Network —Network Analyst Aeronautical —Esri Aeronautical Solution Defense —Esri Defense Solution Foundation —Esri Production Mapping Datareviewer —ArcGIS Data Reviewer Nautical —Esri Nautical Solution Spatial —Spatial Analyst StreetMap —StreetMap Tracking —Tracking Licensing and extensions	String

Return Value

Data Type	Explanation
String	There are three possible returned values for CheckOutExtension: NotInitialized —No desktop license has been set. Unavailable —The requested license is unavailable to be set. CheckedOut —The license has been set successfully.

Code Sample

CheckOutExtension example

Check out 3D extension for use by tools.

class LicenseError(Exception):
    pass

import arcview
import arcpy
from arcpy import env

try:
    if arcpy.CheckExtension("3D") == "Available":
        arcpy.CheckOutExtension("3D")
    else:
        # raise a custom exception
        #
        raise LicenseError

    env.workspace = "D:/GrosMorne"
    arcpy.HillShade_3d("WesternBrook", "wbrook_hill", 300)
    arcpy.Aspect_3d("WesternBrook", "wbrook_aspect")
    arcpy.CheckInExtension("3D")

except LicenseError:
    print "3D Analyst license is unavailable"
except:
    print arcpy.GetMessages(2)