From ...
From: Erik Naggum <clerik@naggum.no>
Subject: Re: Possible bug in inverse Trig funcs in ACL
Date: 1998/09/09
Message-ID: <3114373983670895@naggum.no>#1/1
X-Deja-AN: 389568635
References: <35F67D7B.FB034E2@atdc.northgrum.com> <86ww7dpefi.fsf@g.pet.cam.ac.uk> <35F690FA.E6DBC476@atdc.northgrum.com>
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Newsgroups: comp.lang.lisp.franz,comp.lang.lisp

* Matt Kressel <Matthew_Kressel@atdc.northgrum.com>
| Secondly, why should four or five implementations return the same number,
| precise to twelve or more places, and another differ on the 9th digit?

  one easy answer is that those four or five use the same implementation of
  `acos' and/or the floating-point parser, such as the system math library.
  
#:Erik
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