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ZLAGTM(1) LAPACK auxiliary routine (version 3.2) ZLAGTM(1)

NAME

ZLAGTM - 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

SYNOPSIS

TRANS, N, NRHS, ALPHA, DL, D, DU, X, LDX, BETA, B, LDB )

CHARACTER TRANS INTEGER LDB, LDX, N, NRHS DOUBLE PRECISION ALPHA, BETA COMPLEX*16 B( LDB, * ), D( * ), DL( * ), DU( * ), X( LDX, * )

PURPOSE

ZLAGTM performs a matrix-vector product of the form

ARGUMENTS

Specifies the operation applied to A. = 'N': No transpose, B := alpha * A * X + beta * B
= 'T': Transpose, B := alpha * A**T * X + beta * B
= 'C': Conjugate transpose, B := alpha * A**H * X + beta * B
The order of the matrix A. N >= 0.
The number of right hand sides, i.e., the number of columns of the matrices X and B.
The scalar alpha. ALPHA must be 0., 1., or -1.; otherwise, it is assumed to be 0.
The (n-1) sub-diagonal elements of T.
The diagonal elements of T.
The (n-1) super-diagonal elements of T.
The N by NRHS matrix X. LDX (input) INTEGER The leading dimension of the array X. LDX >= max(N,1).
The scalar beta. BETA must be 0., 1., or -1.; otherwise, it is assumed to be 1.
On entry, the N by NRHS matrix B. On exit, B is overwritten by the matrix expression B := alpha * A * X + beta * B.
The leading dimension of the array B. LDB >= max(N,1).
November 2008 LAPACK auxiliary routine (version 3.2)