how to pass an array to a VB array via COM

[Stefan Schukat]

> -----Original Message-----
> From: python-list-bounces+sschukat=dspace.de at python.org
> [mailto:python-list-bounces+sschukat=dspace.de at python.org]On Behalf Of
> jelle
> Sent: Tuesday, April 26, 2005 12:31 PM
> To: python-list at python.org
> Subject: how to pass an array to a VB array via COM
> 
> 
> Hi,
> 
> I'm trying to script Rhino -the nurbs modeller, not the server soft-
> via COM.
> Which is good fun, except i cant seem to pass arrays to the program.
> I suppose its expecting VB arrays, and is not to keen when i send a
> tuple:
> 
> RS.AddCurve(((1,2,3),(4,5,6),(7,8,9)),3)
> ---
> Traceback (most recent call last):
>   File "<input> ", line 1, in ?
>   File "c:\Python23\lib\site-packages\jf\interface\RhinoScript.py",
> line 48,
> in AddCurve
>     return self._ApplyTypes_(77, 1, (12, 0), ((12, 0), (12, 16)),
> 'AddCurve', None,vaPoints, vaDegree)
>   File "c:\Python23\lib\site-packages\win32com\client\__init__.py",
> line
> 446, in _ApplyTypes_
>     return self._get_good_object_(
> com_error: (-2147352567, 'Exception occurred.', (6, 'RhinoScript_m',
> 'Type
> mismatch in parameter.  One-dimensional array required.', 'C:\\Program
> Files\\Rhinoceros 3.0\\RhinoScript_m.HLP', 393222, 0), None)
> ---
> 
> This is somewhat puzzling, since when i define points in the
> application, these are returned as a tuple of tuples:
> 
> 
> >>>s = RS.GetPoints()
> >>>print s
> ((-7.0, -30.0, 0.0), (15.0, -24.0, 0.0), (-7.0, 12.0, 0.0), (14.0,
> 29.0,
> 0.0), (28.0, 10.0, 0.0), (20.0, 1.0, 0.0))
> 
> I've been searching this list for a solution, but didnt find 
> anything i
> could use. Any ideas?
> 
> Cheers,
> 
> Jelle
> 
> -- 
> http://mail.python.org/mailman/listinfo/python-list
> 

The problem you see here is the automatic calculation of the dimension for 
SafeArrays in Pythoncom. The array shown above could be transported either as 
a 2-dim Array (3x3) or as a 1-dim array (1x3) with elements which are also 1-dim 
arrays. Since the automatic calculation always tries to find the highest dimensionality
the Rhino program will get a 2-Dim array which it does not support. 
In VB you can define the dimension of such a array in Python we must guess. 
I'm just working on a PySafeArray implementation for PythonCom which should 
give you also the opportunity to define the dimension via Python. Until then 
you have no luck. 

	Stefan