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Re: Guarding arithmetic

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Date Thu, 23 Aug 2012 19:30:37 +1000
Subject Re: Guarding arithmetic
From Chris Angelico <rosuav@gmail.com>
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On Thu, Aug 23, 2012 at 7:28 PM, Laszlo Nagy <gandalf@shopzeus.com> wrote:
>> That can work ONLY if the division of 1/0 doesn't raise an exception.
>> This is why the concept of NaN exists; I'm not sure if there's a way
>> to tell Python to return NaN instead of bombing, but it's most likely
>> only possible with floating point, not integer.
>
> For integers, Python will always raise an exception when you try to divide
> by zero. And integers has nothing to do with NaN. Because NaN is meaningful
> for floating point numbers only. Python can be compiled to raise floating
> point exceptions. (On Python 2, this is a compile time option: FPECTL. On
> Python 3, this can be configured runtime:
> http://docs.python.org/library/fpectl.html )

Thanks, that's the sort of thing I meant. I'm not familiar enough with
Python's floating point handler to know those details.

ChrisA

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Thread

Guarding arithmetic Mark Carter <alt.mcarter@gmail.com> - 2012-08-23 02:05 -0700
  Re: Guarding arithmetic Chris Angelico <rosuav@gmail.com> - 2012-08-23 19:16 +1000
    Re: Guarding arithmetic Mark Carter <alt.mcarter@gmail.com> - 2012-08-23 02:22 -0700
    Re: Guarding arithmetic Chris Angelico <rosuav@gmail.com> - 2012-08-23 19:29 +1000
    Re: Guarding arithmetic Mark Carter <alt.mcarter@gmail.com> - 2012-08-23 02:22 -0700
  Re: Guarding arithmetic Laszlo Nagy <gandalf@shopzeus.com> - 2012-08-23 11:23 +0200
    Re: Guarding arithmetic Mark Carter <alt.mcarter@gmail.com> - 2012-08-23 02:47 -0700
    Re: Guarding arithmetic Mark Carter <alt.mcarter@gmail.com> - 2012-08-23 02:47 -0700
  Re: Guarding arithmetic Laszlo Nagy <gandalf@shopzeus.com> - 2012-08-23 11:28 +0200
  Re: Guarding arithmetic Chris Angelico <rosuav@gmail.com> - 2012-08-23 19:30 +1000
  Re: Guarding arithmetic Peter Otten <__peter__@web.de> - 2012-08-23 12:11 +0200
    Re: Guarding arithmetic rusi <rustompmody@gmail.com> - 2012-08-23 10:15 -0700
  Re: Guarding arithmetic Laszlo Nagy <gandalf@shopzeus.com> - 2012-08-23 13:01 +0200
  Re: Guarding arithmetic MRAB <python@mrabarnett.plus.com> - 2012-08-23 12:21 +0100
  Re: Guarding arithmetic Peter Otten <__peter__@web.de> - 2012-08-23 13:28 +0200
  Re: Guarding arithmetic Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-23 15:11 +0100
  Re: Guarding arithmetic Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-08-23 14:49 -0400
  Re: Guarding arithmetic Chris Angelico <rosuav@gmail.com> - 2012-08-24 07:48 +1000

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