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From: Rune Allnor <allnor@tele.ntnu.no>
Newsgroups: comp.soft-sys.matlab
Subject: Re: how to deal with the inversion problem of a huge sparse
Date: Sun, 27 Sep 2009 11:40:43 -0700 (PDT)
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On 27 Sep, 20:23, "Bruno Luong" <b.lu...@fogale.findmycountry> wrote:
> Rune Allnor <all...@tele.ntnu.no> wrote in message <ef773a28-76ca-4e60-b6ee-dc944f4e6...@h30g2000vbr.googlegroups.com>...
>
> > Again, any desire to invert a large matrix is almost always
> > wrong.
>
> Finite element methods, solid mechanics, thermal calculation, fluid dynamic,

These are forward models...

> seismic inversion,

Manual interactive process...

> statistics, data mining, machine learning, data assimilation, weather forecast, quantum mechanics simulation,

Forward models or assembling statistics...

> image reconstruction in medical, photogrammetry, etc... all often call for inversion of huge system of linear equations.

So by a dozen or so applications you mention only a handful
actually are inversion problems, and of those at moset one
or two rely on the inversion of large matrices.

> As far as I know they all seem to work alright.

Most of them do. But the problems you list have very little
in common with the still non-specified problem the OP works
with.

Rune