CGEMMT(3) BLAS routine of NEC Numeric Library Collection CGEMMT(3)
NAME
CGEMMT - performs of the matrix-matrix operations with general matri-
ces and add the result to the upper or lower part of a scalar-matrix
product.
SYNOPSIS
SUBROUTINE CGEMMT( UPLO, TRANSA, TRANSB, N, K, ALPHA, A, LDA, B, LDB,
BETA, C, LDC )
CHARACTER*1 UPLO, TRANSA, TRANSB
INTEGER N, K, LDA, LDB, LDC
COMPLEX ALPHA, BETA
COMPLEX A( LDA, * ), B( LDB, * ), C( LDC, * )
PURPOSE
CGEMMT performs of the matrix-matrix operations with general matrices
and add the result to the upper or lower part of a scalar-matrix prod-
uct. These routines are similar to the CGEMM routines, but they only
access and update a triangular part of the square result matrix.
C := alpha*op( A )*op( B ) + beta*C,
where op( X ) is of
op( X ) = X, op( X ) = X**T or op( X ) = X**H,
alpha and beta are scalars, and A, B and C are matrices, with op( A )
an N by K matrix, op( B ) a K by N matrix and C an N by N matrix.
PARAMETERS
UPLO - CHARACTER*1.
Specifies whether the upper or lower triangular part of the
array C is used. If UPLO = 'U' or 'u', then the upper triangular
part of the array C is used. If UPLO = 'L' or 'l', then the
lower triangular part of the array C is used.
TRANSA - 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.
Unchanged on exit.
TRANSB - CHARACTER*1.
On entry, TRANSB specifies the form of op( B ) to be used in the
matrix multiplication as follows:
TRANSB = 'N' or 'n', op( B ) = B.
TRANSB = 'T' or 't', op( B ) = B**T.
TRANSB = 'C' or 'c', op( B ) = B**H.
Unchanged on exit.
N - INTEGER.
On entry, N specifies the number of rows of the matrix
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.
On entry, ALPHA specifies the scalar alpha. Unchanged on exit.
A - COMPLEX array of DIMENSION ( LDA, ka ), where ka is
K when TRANSA = 'N' or 'n', and is N otherwise. Before
entry with TRANSA = 'N' or 'n', the leading N by K part of the
array A must contain the matrix A, otherwise the leading K by
N 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, N ), otherwise LDA must be at least
max( 1, K ). Unchanged on exit.
B - COMPLEX array of DIMENSION ( LDB, kb ), where kb is
N when TRANSB = 'N' or 'n', and is K otherwise. 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.
BETA - COMPLEX.
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 array of DIMENSION ( LDC, N ).
Before entry with UPLO = 'U' or 'u', the leading N by N upper
triangular part of the array C must contain the upper triangular
part of the matrix C and the strictly lower triangular part of C
is not referenced.
Before entry with UPLO = 'L' or 'l', the leading N by N lower
triangular part of the array C must contain the lower triangular
part of the matrix C and the strictly upper triangular part of C
is not referenced.
When beta is equal to ZERO, C need not be set on input.
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,
N ). Unchanged on exit.
BLAS routine 21 August 2020 CGEMMT(3)