# ztrmm (3) - Linux Man Pages

ztrmm.f -

## SYNOPSIS

### Functions/Subroutines

subroutine ztrmm (SIDE, UPLO, TRANSA, DIAG, M, N, ALPHA, A, LDA, B, LDB)
ZTRMM

## Function/Subroutine Documentation

### subroutine ztrmm (characterSIDE, characterUPLO, characterTRANSA, characterDIAG, integerM, integerN, complex*16ALPHA, complex*16, dimension(lda,*)A, integerLDA, complex*16, dimension(ldb,*)B, integerLDB)

ZTRMM Purpose:

ZTRMM  performs one of the matrix-matrix operations

B := alpha*op( A )*B,   or   B := alpha*B*op( A )

where  alpha  is a scalar,  B  is an m by n matrix,  A  is a unit, or
non-unit,  upper or lower triangular matrix  and  op( A )  is one  of

op( A ) = A   or   op( A ) = A**T   or   op( A ) = A**H.

Parameters:

SIDE

SIDE is CHARACTER*1
On entry,  SIDE specifies whether  op( A ) multiplies B from
the left or right as follows:

SIDE = 'L' or 'l'   B := alpha*op( A )*B.

SIDE = 'R' or 'r'   B := alpha*B*op( A ).

UPLO

UPLO is CHARACTER*1
On entry, UPLO specifies whether the matrix A is an upper or
lower triangular matrix as follows:

UPLO = 'U' or 'u'   A is an upper triangular matrix.

UPLO = 'L' or 'l'   A is a lower triangular matrix.

TRANSA

TRANSA is CHARACTER*1
On entry, TRANSA specifies the form of op( A ) to be used in
the matrix multiplication as follows:

TRANSA = 'N' or 'n'   op( A ) = A.

TRANSA = 'T' or 't'   op( A ) = A**T.

TRANSA = 'C' or 'c'   op( A ) = A**H.

DIAG

DIAG is CHARACTER*1
On entry, DIAG specifies whether or not A is unit triangular
as follows:

DIAG = 'U' or 'u'   A is assumed to be unit triangular.

DIAG = 'N' or 'n'   A is not assumed to be unit
triangular.

M

M is INTEGER
On entry, M specifies the number of rows of B. M must be at
least zero.

N

N is INTEGER
On entry, N specifies the number of columns of B.  N must be
at least zero.

ALPHA

ALPHA is COMPLEX*16
On entry,  ALPHA specifies the scalar  alpha. When  alpha is
zero then  A is not referenced and  B need not be set before
entry.

A

A is COMPLEX*16 array of DIMENSION ( LDA, k ), where k is m
when  SIDE = 'L' or 'l'  and is  n  when  SIDE = 'R' or 'r'.
Before entry  with  UPLO = 'U' or 'u',  the  leading  k by k
upper triangular part of the array  A must contain the upper
triangular matrix  and the strictly lower triangular part of
A is not referenced.
Before entry  with  UPLO = 'L' or 'l',  the  leading  k by k
lower triangular part of the array  A must contain the lower
triangular matrix  and the strictly upper triangular part of
A is not referenced.
Note that when  DIAG = 'U' or 'u',  the diagonal elements of
A  are not referenced either,  but are assumed to be  unity.

LDA

LDA is INTEGER
On entry, LDA specifies the first dimension of A as declared
in the calling (sub) program.  When  SIDE = 'L' or 'l'  then
LDA  must be at least  max( 1, m ),  when  SIDE = 'R' or 'r'
then LDA must be at least max( 1, n ).

B

B is (input/output) COMPLEX*16 array of DIMENSION ( LDB, n ).
Before entry,  the leading  m by n part of the array  B must
contain the matrix  B,  and  on exit  is overwritten  by the
transformed matrix.

LDB

LDB is INTEGER
On entry, LDB specifies the first dimension of B as declared
in  the  calling  (sub)  program.   LDB  must  be  at  least
max( 1, m ).

Author:

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Date:

November 2011

Further Details:

Level 3 Blas routine.

-- Written on 8-February-1989.
Jack Dongarra, Argonne National Laboratory.
Iain Duff, AERE Harwell.
Jeremy Du Croz, Numerical Algorithms Group Ltd.
Sven Hammarling, Numerical Algorithms Group Ltd.

Definition at line 178 of file ztrmm.f.

## Author

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