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[Caml-list] Finding the sign of a float
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Date: -- (:)
From: malc <malc@p...>
Subject: Re: [Caml-list] Finding the sign of a float
On Sat, 1 Feb 2003, John Carr wrote:

>
> > I'm looking for a way, in pure ocaml without having to bail out to C, to
> > tell if a float is negative or not.
> >
> > Just using x < 0.0 won't work, as I need to be able to tell the difference
> > between -0.0 and +0.0. This is for ocaml versions of the C copysign and
> > signbit functions. Any suggestions?
>
> x < 0.0 || (x = 0.0 && 1.0/.x < 0.0)
>
> may be faster than converting the bits to integer, or slower,
> depending on platform and context, and how often you encounter -0.

1.0 /. x = neg_infinity less typing

-- 
mailto:malc@pulsesoft.com
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