Triangular Factorization (trf)
trf (defined in namespace flens::lapack) computes an \(LU\) factorization of a general \(m \times n\) matrix \(A\) using partial pivoting with row interchanges.
The factorization has the form
\[ A = P L U \]where \(P\) is a permutation matrix, \(L\) is lower triangular with unit diagonal elements (lower trapezoidal if \(m > n\)), and \(U\) is upper triangular (upper trapezoidal if \(m < n\)).
Interface
A |
(input/output) real or complex valued GeMatrix |
piv |
(output) integer valued DenseVector |
Notes
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Example: lapack-getrf.
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This is the right-looking Level 3 BLAS version of the algorithm.
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trf is a port of dgetrf and zgetrf. Also this documentation is taken from there.