Re: propose deprecation of generalized-vector-*

[Mike Gran]

From: Noah Lavine <noah.b.lav...@gmail.com>
>Hello,
>>On Wed 23 Jan 2013 13:20, Daniel Llorens <daniel.llor...@bluewin.ch> writes:
>>
>>> In [2]: a = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
>>
>>> In [4]: a[1]
>>> Out[4]: array([4, 5, 6])
>>> In [5]: a[1, 1]
>>> Out[5]: 5
>>>
>>> array-ref can be extended very simply to do that. It accumulates on the
>>> position as it is done now, but if the index list comes up short it
>>> makes a shared array with the remaining axes instead of giving a rank
>>> error. So it shouldn't be any slower than array_ref.
>>
>>It could make sense, yes.  What do others think?  What happens for
>>array-set!?  Care to propose a patch?
>
>
> I haven't worked with the array functionality, so I might be missing
> something, but I don't see why this is natural for array-ref. 
 
One could imagine a Matlab-like syntax where array-ref has to have
the same number of indices as the underlying array, but, if an
index were replaced with a symbol, it would return a slice.
 
if np is [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
(array-ref np 1 1) -> 5
(array-ref np 1 :) -> [4, 5, 6]
(array-ref np : 1) -> [[2], [5], [8]]
 
Or maybe that's already in Scheme. I'll admit I've never done matrices
in scheme.
 
-Mike