From: Marius Vollmer <mvo@zagadka.de>
Cc: bug-guile@gnu.org
Subject: Re: division by 0
Date: Sun, 21 Mar 2004 01:34:27 +0100 [thread overview]
Message-ID: <87r7vnm418.fsf@zagadka.ping.de> (raw)
In-Reply-To: <877jy22d62.fsf@merceron.meteo.fr> (Bernard Urban's message of "03 Mar 2004 15:55:17 +0100")
Bernard Urban <Bernard.Urban@meteo.fr> writes:
> Debian woody on i386.
>
> $ guile
> guile> (version)
> "1.6.4"
> guile> (/ 0)
> +#.#
> guile> (/ 1.0 0)
> +#.#
> guile> (/ 1 0.0)
> +#.#
> guile>(/ 1 0)
> standard input:3:1: In procedure / in expression (/ 1 0):
> standard input:3:1: Numerical overflow
> ABORT: (numerical-overflow)
>
> Type "(backtrace)" to get more information or "(debug)" to enter the debugger.
> guile>
>
> Problem happens in numbers.c, function scm_divide(), where the test
> #line 3274 should not be made.
The 1.7 series should be handling this more correctly. From NEWS:
** There is support for Infinity and NaNs.
Following PLT Scheme, Guile can now work with infinite numbers, and
'not-a-numbers'.
There is new syntax for numbers: "+inf.0" (infinity), "-inf.0"
(negative infinity), "+nan.0" (not-a-number), and "-nan.0" (same as
"+nan.0"). These numbers are inexact and have no exact counterpart.
Dividing by an inexact zero returns +inf.0 or -inf.0, depending on the
sign of the dividend. The infinities are integers, and they answer #t
for both 'even?' and 'odd?'. The +nan.0 value is not an integer and is
not '=' to itself, but '+nan.0' is 'eqv?' to itself.
For example
(/ 1 0.0)
=> +inf.0
(/ 0 0.0)
=> +nan.0
(/ 0)
ERROR: Numerical overflow
Two new predicates 'inf?' and 'nan?' can be used to test for the
special values.
--
GPG: D5D4E405 - 2F9B BCCC 8527 692A 04E3 331E FAF8 226A D5D4 E405
_______________________________________________
Bug-guile mailing list
Bug-guile@gnu.org
http://mail.gnu.org/mailman/listinfo/bug-guile
next prev parent reply other threads:[~2004-03-21 0:34 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-03-03 14:55 division by 0 Bernard Urban
2004-03-21 0:34 ` Marius Vollmer [this message]
2004-03-29 9:09 ` Bernard Urban
2004-04-20 1:21 ` Kevin Ryde
2004-04-20 13:21 ` Bernard Urban
2004-04-20 15:18 ` Bernard Urban
2004-05-10 21:36 ` Marius Vollmer
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: https://www.gnu.org/software/guile/
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87r7vnm418.fsf@zagadka.ping.de \
--to=mvo@zagadka.de \
--cc=bug-guile@gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).