2.2 KiB
FactorizationPLUGeTridRaw
Computes an LU factorization of a general (non-symmetric) tridiagonal N-by-N matrix A using elimination with partial pivoting and 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, and U is upper triangular. LAPACK function GTTRF.
Computing for type matrix
bool matrix::FactorizationPLUGeTridRaw(
matrix& AF, // factored matrix A
long[]& ipiv // pivot indices array
);
Computing for type matrix
bool matrixf::FactorizationPLUGeTridRaw(
matrixf& AF, // factored matrix A
long[]& ipiv // pivot indices array
);
Computing for type matrix
bool matrixc::FactorizationPLUGeTridRaw(
matrixc& AF, // factored matrix A
long[]& ipiv // pivot indices array
);
Computing for type matrix
bool matrixcf::FactorizationPLUGeTridRaw(
matrixcf& AF, // factored matrix A
long[]& ipiv // pivot indices array
);
Parameters
AF
[out] Factored matrix A. The factors L and U from the factorization A = PLU; the unit diagonal elements of L are not stored.
ipiv
[out] Pivot indices array of size N; row i of the matrix A was interchanged with row ipiv[i].
Return Value
Return true if successful, otherwise false in case of an error.
Note
Matrix AF and pivot indices array ipiv[] are raw output of the GTTRF function and can be used for further calculations with methods PLUGeTridLinearEquationsSolution and PLUGeTridCondNumReciprocal.