Linear Algebra Package (LAPACK)
LAPACK website List of subroutine
Many routines for linear algebra. Typical name: XYYZZZ
- X is precision
- YY is type of matrix,
- e.g. GE (general), GB (general banded), GT (general tridiagonal)
- ZZZ is type of operation,
- e.g. SV (solve system), SVX (solve system expert), EV (eigenvalues, vectors), SVD (singularvalues, vectors)
General Dense Matrix System Solver
Ex: DGESV( N, NRHS, A, LDA, IPIV, B, LDB, INFO )
DGESV computes the solution to a real system of linear equations A * X = B, where A is an N-by-N matrix and X and B are N-by-NRHS matrices. The LU decomposition with partial pivoting and row interchanges is used to factor A as A = P * L * U, where P is a permutation matrix, L is unit lower triangular, and U is upper triangular. The factored form of A is then used to solve the system of equations A * X = B.
Tri-diagonal Matrix System Solver
Ex:DGTSV( N, NRHS, DL, D, DU, B, LDB, INFO )
DGTSV solves the equation A*X = B, where A is an n by n tridiagonal matrix, by Gaussian elimination with partial pivoting. Note that the equation A'*X = B may be solved by interchanging the order of the arguments DU and DL.
Band Matrix System Solver
Ex: DGBSV( N, KL, KU, NRHS, AB, LDAB, IPIV, B, LDB, INFO )
DGBSV computes the solution to a real system of linear equations A * X = B, where A is a band matrix of order N with KL subdiagonals and KU superdiagonals, and X and B are N-by-NRHS matrices. The LU decomposition with partial pivoting and row interchanges is used to factor A as A = L * U, where L is a product of permutation and unit lower triangular matrices with KL subdiagonals, and U is upper triangular with KL+KU superdiagonals. The factored form of A is then used to solve the system of equations A * X = B.
Attachments (3)
- Lapack_DGESV.png (21.6 KB) - added by fuji 4 years ago.
- Lapack_DGBSV.png (23.6 KB) - added by fuji 4 years ago.
- Lapack_DGTSV.png (26.0 KB) - added by fuji 4 years ago.
Download all attachments as: .zip