[Numpy-discussion] RFC: out of range slice indexes
Mon Jan 14 13:54:04 CST 2008
Robert Kern wrote:
> Neal Becker wrote:
>> I've never liked that python silently ignores slices with out of range
>> indexes. I believe this is a source of bugs (it has been for me). It
>> goes completely counter to the python philosophy.
>> I vote to ban them from numpy.
>>>>> from numpy import array
>>>>> x = array (xrange (10))
>> Traceback (most recent call last):
>> File "<stdin>", line 1, in <module>
>> IndexError: index out of bounds
>>>>> x[:12] = 2
>> array([2, 2, 2, 2, 2, 2, 2, 2, 2, 2])
>>>>> len (x)
>> Silently ignoring the error x[:12] is a bad idea, IMO. If it meant to
>> _extend_ x to have lenght 12, at least _that_ would be reasonable (but
>> I'm not advocating that position).
>> I believe that out of bounds indexes should always throw IndexError. We
>> can't change that in Python now, but maybe we can in numpy.
> -1. Regardless of the merits if we had a blank slate, there is code that
> depends on this, specifically my code. It simplifies certain operations
> that would otherwise need tedious special case-handling.
More information about the Numpy-discussion