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From: dik@cwi.nl (Dik T. Winter)
Newsgroups: comp.lang.fortran
Subject: Re: MAX function, but carry sign
Message-ID: <3312@charon.cwi.nl>
Date: 13 Apr 91 20:04:37 GMT
References: <282@venice.water.ca.gov> <1991Apr12.151728.12916@craycos.com>
Sender: news@cwi.nl
Organization: CWI, Amsterdam
Lines: 11

In article <1991Apr12.151728.12916@craycos.com> jrbd@craycos.com (James Davies) writes:
 > In article <282@venice.water.ca.gov> rfinch@caldwr.water.ca.gov (Ralph Finch) writes:
 > >a=max(abs(a1),abs(a2)) ! but a has sign of either a1 or a2
 > >
 > 	a = sign(max(abs(a1),abs(a2)), a1+a2)

Except this fails if a1+a2 overflows.  The other solution I saw is better,
although a bit more elaborate.
--
dik t. winter, cwi, amsterdam, nederland
dik@cwi.nl