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Re: So what's happening here?

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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

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Thread

So what's happening here? Paul Appleby <pap@nowhere.invalid> - 2015-06-05 12:46 +0000
  Re: So what's happening here? Fabien <fabien.maussion@gmail.com> - 2015-06-05 14:52 +0200
  Re: So what's happening here? Larry Martell <larry.martell@gmail.com> - 2015-06-05 08:55 -0400
  Re: So what's happening here? Peter Otten <__peter__@web.de> - 2015-06-05 15:09 +0200
  Re: So what's happening here? Paul Appleby <pap@nowhere.invalid> - 2015-06-05 13:11 +0000
    Re: So what's happening here? Gary Herron <gary.herron@islandtraining.com> - 2015-06-05 06:23 -0700
    Re: So what's happening here? Steven D'Aprano <steve@pearwood.info> - 2015-06-05 23:51 +1000
    Re: So what's happening here? Nobody <nobody@nowhere.invalid> - 2015-06-05 15:13 +0100

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