[SciPy-dev] shape_base questions

[Pietro Berkes]

Hi! I was taking a look to the 'shape_base.py' file, and I've got a couple of 
questions/suggestions:

- 'apply_over_axes' won't work, since it cannot find SequenceType on line 15. 
SequenceType was defined in stats/rv2.py and stats/stats.py, where 
'apply_over_axes' is used. I suggest to move the definition

SequenceType = [types.TupleType, types.ListType, Numeric.ArrayType]

together with a predicate function:

def issequence(seq):
   return type(seq) in SequenceType

in scipy_base/type_check.py and then to fix rv2.py, stats.py and 
shape_base.py. By the way: in rv2.py, SequenceType contains array.ArrayType 
and Numeric.ArrayType. Are they different? And if yes, why? 

- 'apply_over_axes'  and 'expand_dims' accept negative axes, while other 
functions don't. Are there design guidelines regarding negative axes? The two 
functions correct negative indices in two different ways:
'apply_over_axes' : axis = len(shape) + axis
'expand_dims'       : axis = len(shape) + axis + 1
I think the first way is the correct one in both cases, at least it would 
match the documentation of both functions.

I could send a patch for these issues... what is the preferred way to do 
this? Should I use the SourceForge page (it appears to be void...)?

Regards,
Pietro.