ZGEMM - perform one of the matrix-matrix operations C :=
alpha*op( A )*op( B ) + beta*C,
SYNOPSIS
SUBROUTINE ZGEMM ( TRANSA, TRANSB, M, N, K, ALPHA, A, LDA,
B, LDB, BETA, C, LDC )
CHARACTER*1 TRANSA, TRANSB
INTEGER M, N, K, LDA, LDB, LDC
COMPLEX*16 ALPHA, BETA
COMPLEX*16 A( LDA, * ), B( LDB, * ), C( LDC, * )
PURPOSE
ZGEMM performs one of the matrix-matrix operations
where op( X ) is one of
op( X ) = X or op( X ) = X' or op( X ) = conjg(
X' ),
alpha and beta are scalars, and A, B and C are matrices,
with op( A ) an m by k matrix, op( B ) a k by n matrix
and C an m by n matrix.
PARAMETERS
TRANSA - CHARACTER*1. On entry, TRANSA specifies the form
of op( A ) to be used in the matrix multiplication as fol
lows:
TRANSA = 'N' or 'n', op( A ) = A.
TRANSA = 'T' or 't', op( A ) = A'.
TRANSA = 'C' or 'c', op( A ) = conjg( A' ).
Unchanged on exit.
TRANSB - CHARACTER*1. On entry, TRANSB specifies the form
of op( B ) to be used in the matrix multiplication as fol
lows:
TRANSB = 'N' or 'n', op( B ) = B.
TRANSB = 'T' or 't', op( B ) = B'.
TRANSB = 'C' or 'c', op( B ) = conjg( B' ).
Unchanged on exit.
On entry, M specifies the number of rows of
the matrix op( A ) and of the matrix C. M
must be at least zero. Unchanged on exit.
N - INTEGER.
On entry, N specifies the number of columns of
the matrix op( B ) and the number of columns of the
matrix C. N must be at least zero. Unchanged on
exit.
K - INTEGER.
On entry, K specifies the number of columns of
the matrix op( A ) and the number of rows of the
matrix op( B ). K must be at least zero.
Unchanged on exit.
ALPHA - COMPLEX*16 .
On entry, ALPHA specifies the scalar alpha.
Unchanged on exit.
A - COMPLEX*16 array of DIMENSION ( LDA, ka
), where ka is
k when TRANSA = 'N' or 'n', and is m other
wise. Before entry with TRANSA = 'N' or 'n', the
leading m by k part of the array A must contain
the matrix A, otherwise the leading k by m part
of the array A must contain the matrix A.
Unchanged on exit.
LDA - INTEGER.
On entry, LDA specifies the first dimension of A as
declared in the calling (sub) program. When TRANSA
= 'N' or 'n' then LDA must be at least max( 1, m
), otherwise LDA must be at least max( 1, k ).
Unchanged on exit.
B - COMPLEX*16 array of DIMENSION ( LDB, kb ),
where kb is
n when TRANSB = 'N' or 'n', and is k other
wise. Before entry with TRANSB = 'N' or 'n', the
leading k by n part of the array B must contain
the matrix B, otherwise the leading n by k part
of the array B must contain the matrix B.
Unchanged on exit.
LDB - INTEGER.
On entry, LDB specifies the first dimension of B as
declared in the calling (sub) program. When TRANSB
= 'N' or 'n' then LDB must be at least max( 1, k
), otherwise LDB must be at least max( 1, n ).
Unchanged on exit.
On entry, BETA specifies the scalar beta. When
BETA is supplied as zero then C need not be set on
input. Unchanged on exit.
C - COMPLEX*16 array of DIMENSION ( LDC, n ).
Before entry, the leading m by n part of the
array C must contain the matrix C, except when
beta is zero, in which case C need not be set on
entry. On exit, the array C is overwritten by
the m by n matrix ( alpha*op( A )*op( B ) +
beta*C ).
LDC - INTEGER.
On entry, LDC specifies the first dimension of C as
declared in the calling (sub) program. LDC
must be at least max( 1, m ). Unchanged on
exit.
Level 3 Blas routine.
-- Written on 8-February-1989. Jack Dongarra,
Argonne National Laboratory. Iain Duff, AERE Har
well. Jeremy Du Croz, Numerical Algorithms Group
Ltd. Sven Hammarling, Numerical Algorithms Group
Ltd.
Man(1) output converted with
man2html