Title:
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A direct solver for finite element matrices requiring $O(N \log N)$ memory places (English) |
Author:
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Vejchodský, Tomáš |
Language:
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English |
Journal:
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Applications of Mathematics 2013 |
Volume:
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Proceedings. Prague, May 15-17, 2013 |
Issue:
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2013 |
Year:
|
|
Pages:
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225-239 |
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Category:
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math |
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Summary:
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We present a method that in certain sense stores the inverse of the stiffness matrix in $O(N\log N)$ memory places, where $N$ is the number of degrees of freedom and hence the matrix size. The setup of this storage format requires $O(N^{3/2})$ arithmetic operations. However, once the setup is done, the multiplication of the inverse matrix and a vector can be performed with $O(N\log N)$ operations. This approach applies to the first order finite element discretization of linear elliptic and parabolic problems in triangular domains, but it can be generalized to higher-order elements, variety of problems, and general domains. The method is based on a special hierarchical enumeration of vertices and on a hierarchical elimination of suitable degrees of freedom. Therefore, we call it hierarchical condensation of degrees of freedom. (English) |
Keyword:
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sparse direct solver |
Keyword:
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hierarchical condensation |
Keyword:
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finite element method |
Keyword:
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sparse matrices |
Keyword:
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algorithm |
MSC:
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65F05 |
MSC:
|
65F50 |
MSC:
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65N30 |
idZBL:
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Zbl 1340.65038 |
idMR:
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MR3204447 |
. |
Date available:
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2017-02-14T09:19:47Z |
Last updated:
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2017-03-20 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/702950 |
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