zlagtm.f - Man Page

SRC/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 (character trans, integer n, integer nrhs, double precision alpha, complex*16, dimension( * ) dl, complex*16, dimension( * ) d, complex*16, dimension( * ) du, complex*16, dimension( ldx, * ) x, integer ldx, double precision beta, complex*16, dimension( ldb, * ) b, integer 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.

Purpose:

``` ZLAGTM performs a matrix-matrix 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

NAG Ltd.

Definition at line 143 of file zlagtm.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

The man page zlagtm(3) is an alias of zlagtm.f(3).

Tue Nov 28 2023 12:08:42 Version 3.12.0 LAPACK