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From: gwyn@smoke.brl.mil (Doug Gwyn)
Newsgroups: comp.lang.c
Subject: Re: Execution time bottleneck: How to speed up execution?
Message-ID: <15181@smoke.brl.mil>
Date: 13 Feb 91 21:15:10 GMT
References: <1991Feb12.233522.5195@Think.COM> <15884.27b919a3@levels.sait.edu.au> <64745@brunix.UUCP>
Organization: U.S. Army Ballistic Research Laboratory, APG, MD.
Lines: 9

In article <64745@brunix.UUCP> gvr@cs.brown.edu (George V. Reilly) writes:
-In article <15884.27b919a3@levels.sait.edu.au> marwk@levels.sait.edu.au (Ray)
-writes:
-> (1) rewrite the sum as Sum = 2 * S{i=1,i=n-1} S{j=i+1,j=n} f(i,j)
->     this cuts the number of calculations in half.
-I can make no sense of this statement.  It's not equivalent to
-the original code.

The idea was right, but he handled the diagonal incorrectly.