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Re: Sparse matrices?
From: |
Ian Searle |
Subject: |
Re: Sparse matrices? |
Date: |
Wed, 18 Jun 1997 08:16:33 -0700 |
Stef Pillaert BK wrote:
>
> Hello,
>
> I'm wondering... is it possible in octave to work with sparse matrices to
> save some space? (if not, is there a chance that it will be in the near
> future?)
>
> Thanks.
>
> Stef address@hidden
Having just added sparse matrices to RLaB (no plug intended). I can
offer some information. It is far more difficult and time consuming than
it looks! Seemingly trivial operations like:
a[i;j] = x;
are difficult to implement... not to mention an efficient
implementation.
I choose compressed row-wise sparse storage. With the aid of hindsight,
I might have choosed compressed column-wise sparse storage.
Then, once sparse structures and operations are implemented comes the
joy of finding an efficient, and free sparse non-symmetric solver, and
graph partitioning/re-ordering packages.
All in all, a considerable amount of work. I was very fortunate that
some users (one in particular) have very good educations in linear
algebra.
Cheers,
--
Ian Searle
address@hidden
- Sparse matrices?, Stef Pillaert BK, 1997/06/18
- Re: Sparse matrices?,
Ian Searle <=