From: gautier_niouzes@hotmail.com
Cc: nma@12000.org
Subject: Re: Does Ada need elemental functions to make it suitable for scientific work?
Date: Wed, 11 Jul 2012 01:41:50 -0700 (PDT)
Date: 2012-07-11T01:41:50-07:00 [thread overview]
Message-ID: <c769ecea-8650-4bab-8c2b-6f0799b6dbe1@googlegroups.com> (raw)
In-Reply-To: <ad14f9ab-ed36-4101-aef5-caee6e315dcc@googlegroups.com>
Ada novice :
> In finite element formulations, one will usually end up with sparse matrices. I do not know whether Ada has support for such matrices. Matlab for instance has dedicated solver(s) for the system Ax=b when A is a sparse matrix. I think beside storage consideration, sparse matrices solvers are faster (I can be wrong though).
They are fast but it all depends on the problem and the conditioning of the matrix. Sometimes you are also well served by band matrices and a good algorithm to rearrange the node numbering so that nodes that are close in the mesh end up with close indices and then the matrix has fewer non-zero diagonal bands around the main diagonal.
Choice of solvers for sparse matrices are limited - because they need to. e.g. a LU decomposition would require to know where are the non-zeros for having L and U stored as sparse matrices. And probably they are not sparse at all...
You find a sparse matrix package and appropriate solvers in Mathpaqs pack there:
http://sf.net/projects/mathpaqs/
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Gautier's Ada programming -- http://gautiersblog.blogspot.com/search/label/Ada
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next prev parent reply other threads:[~2012-07-11 21:48 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-09 23:27 Does Ada need elemental functions to make it suitable for scientific work? Nasser M. Abbasi
[not found] ` <d78nv7dhf88bqv7hrd9eft231a4h2scs10@invalid.netcom.com>
2012-07-10 4:22 ` Nasser M. Abbasi
2012-07-10 14:26 ` Marco
2012-07-10 4:24 ` gautier_niouzes
2012-07-10 5:22 ` Ada novice
2012-07-10 7:27 ` Dmitry A. Kazakov
2012-07-10 8:06 ` gautier_niouzes
[not found] ` <637de084-0e71-4077-a1c5-fc4200cad3cf@googlegroups.com>
2012-07-10 8:39 ` Nasser M. Abbasi
2012-07-10 8:58 ` Ada novice
2012-07-10 9:07 ` Dmitry A. Kazakov
2012-07-10 9:21 ` Nasser M. Abbasi
2012-07-10 9:26 ` Nasser M. Abbasi
2012-07-10 9:50 ` Dmitry A. Kazakov
2012-07-20 1:56 ` Randy Brukardt
2012-07-20 21:49 ` Adam Beneschan
2012-07-12 0:31 ` robin.vowels
2012-07-12 7:12 ` Dmitry A. Kazakov
2012-07-29 13:39 ` Robin Vowels
2012-07-29 14:22 ` Dmitry A. Kazakov
2012-07-29 20:54 ` glen herrmannsfeldt
[not found] ` <apib1897s56dkultqmfl3emvk1os3tfdak@invalid.netcom.com>
2012-07-30 4:15 ` glen herrmannsfeldt
[not found] ` <nfhd181tv9u87mcqfb7rgd8lm48ihr9f4r@invalid.netcom.com>
2012-07-31 8:53 ` MATRIX MULTIPLICATION Robin Vowels
2012-07-31 9:05 ` Robin Vowels
2012-07-30 0:49 ` Does Ada need elemental functions to make it suitable for scientific work? Robin Vowels
2012-07-12 0:22 ` robin.vowels
2012-07-20 1:51 ` Randy Brukardt
2012-07-29 13:53 ` Robin Vowels
2012-07-29 15:51 ` J-P. Rosen
2012-07-29 16:07 ` Dmitry A. Kazakov
2012-07-29 20:30 ` Simon Wright
2012-07-29 20:59 ` glen herrmannsfeldt
2012-07-29 21:44 ` J-P. Rosen
2012-07-29 22:54 ` Simon Wright
2012-07-30 0:53 ` Robin Vowels
2012-07-30 2:20 ` Shmuel Metz
2012-07-10 12:46 ` Brian Drummond
2012-07-10 11:06 ` Simon Wright
2012-07-10 11:59 ` Georg Bauhaus
2012-07-10 12:20 ` Brian Drummond
2012-07-10 19:52 ` Ada novice
2012-07-11 8:41 ` gautier_niouzes [this message]
2012-07-11 9:42 ` Ken Thomas
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