question about numpy, subclassing, and a DeprecationWarning

[Jason Swails]

Hello,

I'm running into an unexpected issue in a program I'm writing, and I was
hoping someone could provide some clarification for me.  I'm trying to
subclass numpy.ndarray (basically create a class to handle a 3D grid).
 When I instantiate a numpy.ndarray, everything works as expected.  When I
call numpy.ndarray's constructor directly within my subclass, I get a
deprecation warning about object.__init__ not taking arguments.  Presumably
this means that ndarray's __init__ is somehow (for some reason?) calling
object's __init__...

This is some sample code:

>>> import numpy as np
>>> class derived(np.ndarray):
...     def __init__(self, stuff):
...             np.ndarray.__init__(self, stuff)
...
>>> l = derived((2,3))
__main__:3: DeprecationWarning: object.__init__() takes no parameters
>>> l
derived([[  8.87744455e+159,   6.42896975e-109,   5.56218818e+180],
       [  1.79996515e+219,   2.41625066e+198,   5.15855295e+307]])
>>>

Am I doing something blatantly stupid?  Is there a better way of going
about this?  I suppose I could create a normal class and just put the grid
points in a ndarray as an attribute to the class, but I would rather
subclass ndarray directly (not sure I have a good reason for it, though).
 Suggestions on what I should do?

Thanks!
Jason
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