zlagtm.f man page

zlagtm.f —

Synopsis

Functions/Subroutines

subroutine zlagtm (TRANS, N, NRHS, ALPHA, DL, D, DU, X, LDX, BETA, B, LDB)
ZLAGTM 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.

Function/Subroutine Documentation

subroutine zlagtm (characterTRANS, integerN, integerNRHS, double precisionALPHA, complex*16, dimension( * )DL, complex*16, dimension( * )D, complex*16, dimension( * )DU, complex*16, dimension( ldx, * )X, integerLDX, double precisionBETA, complex*16, dimension( ldb, * )B, integerLDB)

ZLAGTM 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.

Purpose:

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.

Parameters:

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**T * X + beta * B
= 'C':  Conjugate transpose, B := alpha * A**H * X + beta * B

N

N is INTEGER
The order of the matrix A.  N >= 0.

NRHS

NRHS is INTEGER
The number of right hand sides, i.e., the number of columns
of the matrices X and B.

ALPHA

ALPHA is DOUBLE PRECISION
The scalar alpha.  ALPHA must be 0., 1., or -1.; otherwise,
it is assumed to be 0.

DL

DL is COMPLEX*16 array, dimension (N-1)
The (n-1) sub-diagonal elements of T.

D

D is COMPLEX*16 array, dimension (N)
The diagonal elements of T.

DU

DU is COMPLEX*16 array, dimension (N-1)
The (n-1) super-diagonal elements of T.

X

X is COMPLEX*16 array, dimension (LDX,NRHS)
The N by NRHS matrix X.

LDX

LDX is INTEGER
The leading dimension of the array X.  LDX >= max(N,1).

BETA

BETA is DOUBLE PRECISION
The scalar beta.  BETA must be 0., 1., or -1.; otherwise,
it is assumed to be 1.

B

B is COMPLEX*16 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.

LDB

LDB is INTEGER
The leading dimension of the array B.  LDB >= max(N,1).

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

September 2012

Definition at line 145 of file zlagtm.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

zlagtm(3) is an alias of zlagtm.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK