How to check if a Polygon is inside another Polygon w/o using Select By Location?

Question

Happy New Year everyone!!

I need your help on this after googling for days.

I am using ArcGIS 9.3 and want to develop a Python code (Python version = 2.6) to recognize if a polygon is inside another polygon. These polygons are created by codes and not in any shapefiles or feature class. Therefore, I don't want to create a new shapefile to just use Select By Location.
I wish there is something like: aPolygon.contains(aPolygon) = True/False

I tried shapely.geometry but ArcToolbox doesn't recognize this line: "from shapely.geometry import Polygon". Shapely can do the topological relationship very simple.

Any helps is appreciated.

bharold · Answer

Hi

Not much help at 9.3 I know, but ArcPy geometry objects have a "contains" method:

http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Polygon/000v000000n1000000/

Regards

ChrisSnyder · Answer

In v10 you would probably have to install any modules you wanted to use via v10 in C:\Python26\ArcGIS10.0 folder rather than the default C:\Python26. Note the similar contents of C:\Python26\ArcGIS10.0\Lib and C:\Python26\Lib.

TrungTran · Answer

Thanks Vara and Dan.

Actually, I can do with VBA but just want to do this in Python because I have some other functions in Python as well.

This command "From shapely.geometry import Polygon" was understood in Python Shell. However, when I created a script and ran it through ArcToolbox, the geoprocessing message window kept saying 
--------------------
<type 'exceptions Import.Error'>: "No module named shapely.geometry
Fail to execute (test)."
--------------------

Any thoughts?
Thanks.