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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 23:41 +0000
Organization A noiseless patient Spider
Message-ID <kg6b9d$sj2$1@dont-email.me> (permalink)
References <kg5sog$lfb$1@dont-email.me><mailman.2191.1361478337.2939.python-list@python.org><kg67l7$bm8$1@dont-email.me> <mailman.2209.1361487258.2939.python-list@python.org>

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"Oscar Benjamin" <oscar.j.benjamin@gmail.com> wrote in

> Then you want operator.pow:
>
>>>> import operator
>>>> operator.pow(3, 2)
> 9
>
> math.pow is basically the (double)pow(double, double) function from
> the underlying C library. operator.pow(a, b) is precisely the same as
> a**b.

So how is operator.pow() different from just pow()?

> There's no need to use strings if you're working with integers in
> Python. The results with int (not float) will be exact and will not
> overflow since Python's ints have unlimited range (unless your machine
> runs out of memory but that only happens with *really* big integers).

Yes, that's the idea. I haven't really used Python before, so was just 
kicking the tyres a bit and got some odd results. This forum has been great 
though.

> If you want to do computations with non-integers and high precision,
> take a look at the decimal and fractions modules.
> http://docs.python.org/2/library/decimal.html
> http://docs.python.org/2/library/fractions.html
>
> There is also a good third party library, sympy, for more complicated
> exact algebra:
> http://sympy.org/en/index.html

Thanks a lot for the references, I'll definitely check them out.

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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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