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Date: Fri, 5 Jun 2015 08:55:09 -0400
Subject: Re: So what's happening here?
From: Larry Martell <larry.martell@gmail.com>
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On Fri, Jun 5, 2015 at 8:46 AM, Paul Appleby <pap@nowhere.invalid> wrote:
> I saw somewhere on the net that you can copy a list with slicing. So
> what's happening when I try it with a numpy array?
>
>>>> a = numpy.array([1,2,3])
>>>> b = a[:]
>>>> a is b
> False
>>>> b[1] = 9
>>>> a
> array([1, 9, 3])

is is identity testing, == is equality testing

>>> a = numpy.array([1,2,3])
>>> b = a[:]
>>> a == b
array([ True,  True,  True], dtype=bool)
>>> id(a)
4510409872
>>> id(b)
4510410192