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[Caml-list] floating point input/conversion
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Date: -- (:)
From: Pierre Weis <Pierre.Weis@i...>
Subject: Re: [Caml-list] floating point input/conversion
> Stefan Ratschan wrote:
> >For the functions float_of_string and read_float the OCaml manual is
> >very vague: "Convert the given string to a float".
> >
> >In fact, this sentence is wrong. For example, the number 0.1 does not
> >have a floating point representation, only approximations to it.
> >
> 
> Probably worst is the conversion from num to float (Num.float_of_num) 
> which goes (or at least used to, I did not check 3.08.1) through
> decimal representation as a string and is therefore not in constant time
> as it could. This prevents a good implementation of what is called "lazy 
> rational number" (you compute a float, but if it is not precise enough, 
> then you compute an exact rational number)
> 
> -- 
> Christophe Raffalli

If you have a patch to perform the conversion in linear time, we will
be more than happy to incorporate it into the library.

Thanks in advance,

-- 
Pierre Weis

INRIA, Projet Cristal, http://pauillac.inria.fr/~weis

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