Re: Who uses clapack?

From: Greg Lindahl (lindahl_at_pbm.com)
Date: 12/10/04 

Date: 10 Dec 2004 15:17:50 -0800

In article <41BA2BB2.6060003@telus.net>,
Jentje Goslinga <goslinga@telus.net> wrote:

> Currently this requires two function calls
> between which the all important norm information is truncated
> from 80 bits accuracy to 64 on a PC for example.

Wow. I can't believe anyone would post this to sci.math.num-analysis!
I thought that non-explicit use of extended precision variables was
universally considered to be a dumb idea. If you want explicit use
of extended precision with LAPACK, you need extra functions.

BTW, modern compilers on PCs generally default to using SSE2
instructions on modern PC cpus, hence no more extended precision
unless you ask for it. This became true soon after the Pentium 4 was
released, which was a few years ago.

-- greg