Difference between revisions of "Solving sparse systems"

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(Created page with "There are many methods available for solving sparse systems. We compare some of them here.")
 
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There are many methods available for solving sparse systems. We compare some of them here.
 
There are many methods available for solving sparse systems. We compare some of them here.
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Mathematica has the following methods available (https://reference.wolfram.com/language/ref/LinearSolve.html#DetailsAndOptions)
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* direct: banded, cholesky, multifrontal (direct sparse LU)
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* iterative: Krylov
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Matlab has the following methods:
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* direct: https://www.mathworks.com/help/matlab/ref/mldivide.html#bt42omx_head
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* iterative: https://www.mathworks.com/help/matlab/math/systems-of-linear-equations.html#brzoiix, including bicgstab, gmres
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Eigen has the following methods: (https://eigen.tuxfamily.org/dox-devel/group__TopicSparseSystems.html)
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* direct: sparse LU
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* iterative: bicgstab, cg
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Solving a simple sparse system $A x = b$ with $A = \begin{bmatrix} \ddots & \ddots & \ddots && \\ & 1 & 1 & 1 & \\ && \ddots & \ddots & \ddots$ and $b = \begin{bmatrix} 1 \\ \vdots \\ 1 \end{bmatrix}$ with dimension $n$
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has the following timings:

Revision as of 13:50, 15 March 2017

There are many methods available for solving sparse systems. We compare some of them here.

Mathematica has the following methods available (https://reference.wolfram.com/language/ref/LinearSolve.html#DetailsAndOptions)

  • direct: banded, cholesky, multifrontal (direct sparse LU)
  • iterative: Krylov

Matlab has the following methods:

Eigen has the following methods: (https://eigen.tuxfamily.org/dox-devel/group__TopicSparseSystems.html)

  • direct: sparse LU
  • iterative: bicgstab, cg

Solving a simple sparse system $A x = b$ with $A = \begin{bmatrix} \ddots & \ddots & \ddots && \\ & 1 & 1 & 1 & \\ && \ddots & \ddots & \ddots$ and $b = \begin{bmatrix} 1 \\ \vdots \\ 1 \end{bmatrix}$ with dimension $n$ has the following timings: