Newsgroups: comp.sys.next
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!batcomputer!theory.tn.cornell.edu!finn
From: finn@theory.tn.cornell.edu (Lee Samuel Finn)
Subject: Computing with complex numbers
Message-ID: <1991Mar18.232133.163@batcomputer.tn.cornell.edu>
Summary: High system time with complex numbers in Absoft FORTRAN
Keywords: FORTRAN, Complex numbers, high system time
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Organization: Cornell Theory Center
Distribution: usa
Date: Mon, 18 Mar 1991 23:21:33 GMT

In doing straight arithmetic calculations (no trancendentals) on
complex numbers using Absoft FORTRAN, I've noted a huge overhead
credited to system time. If I do the real and imaginary calculations 
seperately, I find that the overhead disappears. Does anyone have
a clue as to what is going on? Are there 68882 instructions that do
complex arithmetic that are trapped in the kernel on an '040? 

Thanks in advance,

lsf@astrosun.tn.cornell.edu