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Re: Confusing math problem

From "Schizoid Man" <schiz_man@21stcentury.com>
Newsgroups comp.lang.python
Subject Re: Confusing math problem
Date 2013-02-21 22:44 +0000
Organization A noiseless patient Spider
Message-ID <kg67ul$d4v$1@dont-email.me> (permalink)
References <kg5sog$lfb$1@dont-email.me> <mailman.2193.1361479569.2939.python-list@python.org>

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"Chris Angelico" <rosuav@gmail.com> wrote in

<snip>

> First, are you aware that ** will return int (or sometimes long on
> 2.7.3), while math.pow() will return a float? That may tell you why
> you're seeing differences. That said, though, I wasn't able to
> replicate your result using 2.7.3 and 3.3.0 both on Windows - always
> 9183, indicating 618 of the powers are considered equal. But in
> theory, at least, what you're seeing is that 37 of them compare
> different in floating point on your Mac build. Something to consider:
>
> print(set(result1)-set(result2))

No, I was aware to be honest. I thought ** was just short hand for 
math.pow(). Since ** is the integer operation, I suppose ^ doesn't work as 
an exponent function in Python?

I compared the difference and got a large blob of numbers. To make a proper 
comparison I'll need to compare the base and exponent for which the numbers 
are different rather than the numbers themselves. I'm following Dave's 
suggestion of determining the symmetric difference of the sets.

Thanks for the help.

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Thread

Confusing math problem "Schizoid Man" <schiz_man@21stcentury.com> - 2013-02-21 19:33 +0000
  Re: Confusing math problem Dave Angel <davea@davea.name> - 2013-02-21 15:25 -0500
    Re: Confusing math problem "Schizoid Man" <schiz_man@21stcentury.com> - 2013-02-21 22:39 +0000
      Re: Confusing math problem Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-02-21 22:53 +0000
        Re: Confusing math problem "Schizoid Man" <schiz_man@21stcentury.com> - 2013-02-21 23:41 +0000
          Re: Confusing math problem Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-02-22 00:04 +0000
          Re: Confusing math problem Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-21 17:19 -0700
    Re: Confusing math problem "Schizoid Man" <schiz_man@21stcentury.com> - 2013-02-21 23:39 +0000
  Re: Confusing math problem Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-21 13:42 -0700
  Re: Confusing math problem Chris Angelico <rosuav@gmail.com> - 2013-02-22 07:46 +1100
    Re: Confusing math problem "Schizoid Man" <schiz_man@21stcentury.com> - 2013-02-21 22:44 +0000
      Re: Confusing math problem Chris Angelico <rosuav@gmail.com> - 2013-02-22 11:29 +1100
      Re: Confusing math problem Dave Angel <davea@davea.name> - 2013-02-21 21:19 -0500
  Re: Confusing math problem Dave Angel <davea@davea.name> - 2013-02-21 15:49 -0500
  Re: Confusing math problem Chris Angelico <rosuav@gmail.com> - 2013-02-22 08:23 +1100
    Re: Confusing math problem Peter Pearson <ppearson@nowhere.invalid> - 2013-02-21 21:59 +0000
      Re: Confusing math problem Chris Angelico <rosuav@gmail.com> - 2013-02-22 09:11 +1100
      Re: Confusing math problem Dave Angel <davea@davea.name> - 2013-02-21 17:33 -0500
      Re: Confusing math problem Chris Angelico <rosuav@gmail.com> - 2013-02-22 10:15 +1100
    Re: Confusing math problem Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-22 09:16 +0000
      Re: Confusing math problem Serhiy Storchaka <storchaka@gmail.com> - 2013-02-22 13:48 +0200
  Re: Confusing math problem Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-22 09:27 +0000

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