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LAPACK
3.7.0
LAPACK: Linear Algebra PACKage
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subroutine slagtm | ( | character | TRANS, |
integer | N, | ||
integer | NRHS, | ||
real | ALPHA, | ||
real, dimension( * ) | DL, | ||
real, dimension( * ) | D, | ||
real, dimension( * ) | DU, | ||
real, dimension( ldx, * ) | X, | ||
integer | LDX, | ||
real | BETA, | ||
real, dimension( ldb, * ) | B, | ||
integer | LDB | ||
) |
SLAGTM performs a matrix-matrix product of the form C = αAB+βC, where A is a tridiagonal matrix, B and C are rectangular matrices, and α and β are scalars, which may be 0, 1, or -1.
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SLAGTM performs a matrix-vector product of the form B := alpha * A * X + beta * B where A is a tridiagonal matrix of order N, B and X are N by NRHS matrices, and alpha and beta are real scalars, each of which may be 0., 1., or -1.
[in] | TRANS | TRANS is CHARACTER*1 Specifies the operation applied to A. = 'N': No transpose, B := alpha * A * X + beta * B = 'T': Transpose, B := alpha * A'* X + beta * B = 'C': Conjugate transpose = Transpose |
[in] | N | N is INTEGER The order of the matrix A. N >= 0. |
[in] | NRHS | NRHS is INTEGER The number of right hand sides, i.e., the number of columns of the matrices X and B. |
[in] | ALPHA | ALPHA is REAL The scalar alpha. ALPHA must be 0., 1., or -1.; otherwise, it is assumed to be 0. |
[in] | DL | DL is REAL array, dimension (N-1) The (n-1) sub-diagonal elements of T. |
[in] | D | D is REAL array, dimension (N) The diagonal elements of T. |
[in] | DU | DU is REAL array, dimension (N-1) The (n-1) super-diagonal elements of T. |
[in] | X | X is REAL array, dimension (LDX,NRHS) The N by NRHS matrix X. |
[in] | LDX | LDX is INTEGER The leading dimension of the array X. LDX >= max(N,1). |
[in] | BETA | BETA is REAL The scalar beta. BETA must be 0., 1., or -1.; otherwise, it is assumed to be 1. |
[in,out] | B | B is REAL array, dimension (LDB,NRHS) On entry, the N by NRHS matrix B. On exit, B is overwritten by the matrix expression B := alpha * A * X + beta * B. |
[in] | LDB | LDB is INTEGER The leading dimension of the array B. LDB >= max(N,1). |
Definition at line 147 of file slagtm.f.