From: "François Pottier" <francois.pottier@inria.fr>
To: Andreas Rossberg <rossberg@mpi-sws.org>,
Kenichi Asai <asai@is.ocha.ac.jp>
Cc: caml-list@inria.fr
Subject: Re: [Caml-list] string_of_float (0.1 +. 0.2)
Date: Wed, 15 Jun 2022 09:00:38 +0200 [thread overview]
Message-ID: <1c2d63bb-877c-f40a-d228-f4b877e61b54@inria.fr> (raw)
In-Reply-To: <43238522-BFA7-4F89-8F91-9D95893A9D74@mpi-sws.org>
Hi,
Le 15/06/2022 à 08:22, Andreas Rossberg a écrit :
> The OCaml manual does not say what the default is, but it appears to
be .6 for printf (like in C), while string_of_float is equivalent to
(sprintf "%.12g”) and the REPL uses .18 (which is the maximum meaningful
decimal precision for 64 bit floats):
Indeed, the implementation of string_of_float uses "%.12g".
The manual says that string_of_float returns "the" string representation
of a
floating-point number. I would claim that there is a problem here -- either
the manual should warn that there is a potential loss of information, or the
code should be fixed so as to lose no information.
--
François Pottier
francois.pottier@inria.fr
http://cambium.inria.fr/~fpottier/
next prev parent reply other threads:[~2022-06-15 7:00 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-15 1:59 Kenichi Asai
2022-06-15 6:22 ` Andreas Rossberg
2022-06-15 7:00 ` François Pottier [this message]
2022-06-15 14:07 ` Gabriel Scherer
2022-06-15 14:25 ` Daniel Bünzli
2022-06-16 1:45 ` Kenichi Asai
2022-06-16 6:24 ` Oleg
2022-06-16 9:01 ` Andreas Rossberg
2022-06-16 9:14 ` [Caml-list] unsubscribe Jean-Denis EIDEN JEAN-DENIS
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