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HSL_MA97 Sparse symmetric system using OpenMP

HSL_MA97 uses a direct method to solve large sparse symmetric linear systems of equations $AX=B$. This package optionally uses OpenMP and is designed to achieve bit-compatible results regardless of the number of threads used. It computes the sparse factorization

or

where $L^{\star }=L^T$ (real symmetric or complex symmetric) or $L^{\star }=L^H$ (complex Hermitian, where $L^H$ denotes the conjugate transpose of $L$), $P$ is a permutation matrix, $L$ is lower triangular, and $D$ is block diagonal with blocks of size $1\times 1$ and $2\times 2$.

If $A$ is large, bit-compatible answers are not required, we recommend using HSL_MA86 or HSL_MA87 instead for better efficiency.

.