[Haskell-cafe] C's fmod in Haskell

Thomas Conway drtomc at gmail.com
Mon Sep 24 18:55:58 EDT 2007

On 9/24/07, Henning Thielemann <lemming at henning-thielemann.de> wrote:
> Unfortunately, properFraction doesn't work well with negative numbers.

This old chestnut! It's a common problem in practice. As I recall, the
behaviour of C's % operator allows implementations to yield either
behaviour.  I just checked ISO 9899:1999 which defines fmod. It
specifies that the result of fmod(x,y) should have the same sign as x.

Thomas Conway
drtomc at gmail.com

Silence is the perfectest herald of joy:
I were but little happy, if I could say how much.

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