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Re: Why does 1**2**3**4**5 raise a MemoryError?

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On 03/31/2013 02:56 AM, morphex wrote:
> Hi.
>
> I was just doodling around with the python interpreter today, and here is the dump from the terminal:
>
> morphex@laptop:~$ python
> Python 2.7.3 (default, Sep 26 2012, 21:53:58)
> [GCC 4.7.2] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>>>> 1**2
> 1
>>>> 1**2**3
> 1
>>>> 1**2**3**4
> 1L
>>>> 1**2**3**4**5
> Traceback (most recent call last):
>    File "<stdin>", line 1, in <module>
> MemoryError
>>>>
>
> Does anyone know why this raises a MemoryError?  Doesn't make sense to me.
>
>

Perhaps you didn't realize that the expression will be done from right 
to left.  So first it calculates 4**5 which is 1024

Then it calculates 3**1024, which has 488 digits.  then it calculates 2 
to that power, which is a number large enough to boggle the mind.  That 
number's storage needs makes a few gigabytes seem like a molecule in the 
ocean.

Anyway, it never gets around to doing the 1**  part.

On the other hand, perhaps you wanted to do a different calculation:

 >>> ((((1**2)**3)**4)**5)
1






-- 
DaveA

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Thread

Why does 1**2**3**4**5 raise a MemoryError? morphex <morphex@gmail.com> - 2013-03-30 23:56 -0700
  Re: Why does 1**2**3**4**5 raise a MemoryError? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-03-31 07:33 +0000
    Re: Why does 1**2**3**4**5 raise a MemoryError? Dave Angel <davea@davea.name> - 2013-03-31 03:48 -0400
    Re: Why does 1**2**3**4**5 raise a MemoryError? morphex <morphex@gmail.com> - 2013-03-31 05:07 -0700
      Re: Why does 1**2**3**4**5 raise a MemoryError? Dave Angel <d@davea.name> - 2013-03-31 08:43 -0400
        Re: Why does 1**2**3**4**5 raise a MemoryError? Roy Smith <roy@panix.com> - 2013-03-31 09:15 -0400
          Re: Why does 1**2**3**4**5 raise a MemoryError? Jason Swails <jason.swails@gmail.com> - 2013-03-31 10:03 -0400
      Re: Why does 1**2**3**4**5 raise a MemoryError? Roy Smith <roy@panix.com> - 2013-03-31 09:04 -0400
      Re: Why does 1**2**3**4**5 raise a MemoryError? Tim Roberts <timr@probo.com> - 2013-04-01 21:45 -0700
        Re: Why does 1**2**3**4**5 raise a MemoryError? Chris Angelico <rosuav@gmail.com> - 2013-04-02 17:16 +1100
        Re: Why does 1**2**3**4**5 raise a MemoryError? Dan Sommers <dan@tombstonezero.net> - 2013-04-02 12:56 +0000
    Re: Why does 1**2**3**4**5 raise a MemoryError? Roy Smith <roy@panix.com> - 2013-03-31 08:59 -0400
  Re: Why does 1**2**3**4**5 raise a MemoryError? Dave Angel <davea@davea.name> - 2013-03-31 03:34 -0400
    Re: Why does 1**2**3**4**5 raise a MemoryError? "Alex" <foo@email.invalid> - 2013-03-31 22:06 +0000
      Re: Why does 1**2**3**4**5 raise a MemoryError? Chris Angelico <rosuav@gmail.com> - 2013-04-01 09:28 +1100
        Re: Why does 1**2**3**4**5 raise a MemoryError? "Alex" <foo@email.invalid> - 2013-04-01 00:39 +0000
          Re: Why does 1**2**3**4**5 raise a MemoryError? Chris Angelico <rosuav@gmail.com> - 2013-04-01 11:58 +1100
          Re: Why does 1**2**3**4**5 raise a MemoryError? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-04-01 04:16 +0000
            Re: Why does 1**2**3**4**5 raise a MemoryError? Roy Smith <roy@panix.com> - 2013-04-01 07:48 -0400
          Re: Why does 1**2**3**4**5 raise a MemoryError? Nobody <nobody@nowhere.com> - 2013-04-02 08:40 +0100
      Re: Why does 1**2**3**4**5 raise a MemoryError? Chris Angelico <rosuav@gmail.com> - 2013-04-01 09:32 +1100
      Re: Why does 1**2**3**4**5 raise a MemoryError? Dave Angel <davea@davea.name> - 2013-03-31 18:34 -0400

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