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Author skrah
Recipients Arfrever, christian.heimes, georg.brandl, loewis, mark.dickinson, meador.inge, ncoghlan, pitrou, python-dev, skrah, vstinner
Date 2012-08-10.20:53:40
SpamBayes Score -1.0
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Message-id <1344632022.73.0.465608137429.issue15573@psf.upfronthosting.co.za>
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Martin v. Loewis <report@bugs.python.org> wrote:
> Sure: someone would have to make a proposal what exactly that is.
> IMO, the 3.2 definition *was* simple, but apparently it was considered
> too simple.

It was simply broken in multiple ways. Example:

>>> from numpy import *
>>> x = array([1,2,3,4,5], dtype='B')
>>> y = array([5,4,3,2,1], dtype='B')
>>> z = y[::-1]
>>> 
>>> x == z
array([ True,  True,  True,  True,  True], dtype=bool)
>>> memoryview(x) == memoryview(z)
False
Segmentation fault


I'm not even talking about the segfault here. Note that x == z, but
memoryview(x) != memoryview(z), because the logical structure is
not taken into account.

Likewise, one could construct cases where one array contains a float
NaN and the other an integer that happens to have the same bit pattern.

The arrays would not be equal, but their memoryviews would be equal.



> So either Stefan gets to define his view of equality, or
> somebody else needs to make a (specific) counter-proposal.

The view is defined by the PEP that clearly models NumPy. I'm curious what
counter-proposal will work with NumPy and PIL.
History
Date User Action Args
2012-08-10 20:53:43skrahsetrecipients: + skrah, loewis, georg.brandl, mark.dickinson, ncoghlan, pitrou, vstinner, christian.heimes, Arfrever, meador.inge, python-dev
2012-08-10 20:53:42skrahsetmessageid: <1344632022.73.0.465608137429.issue15573@psf.upfronthosting.co.za>
2012-08-10 20:53:42skrahlinkissue15573 messages
2012-08-10 20:53:40skrahcreate