dsymm (l)  Linux Man Pages
dsymm: performs one of the matrixmatrix operations C := alpha*A*B + beta*C,
NAME
DSYMM  performs one of the matrixmatrix operations C := alpha*A*B + beta*C,SYNOPSIS
 SUBROUTINE DSYMM(SIDE,UPLO,M,N,ALPHA,A,LDA,B,LDB,BETA,C,LDC)
 DOUBLE PRECISION ALPHA,BETA
 INTEGER LDA,LDB,LDC,M,N
 CHARACTER SIDE,UPLO
 DOUBLE PRECISION A(LDA,*),B(LDB,*),C(LDC,*)
PURPOSE
DSYMM performs one of the matrixmatrix operations
or
C :=
where alpha and beta are scalars, A is a symmetric matrix and B and
C are m by n matrices.
ARGUMENTS
 SIDE  CHARACTER*1.

On entry, SIDE specifies whether the symmetric matrix A
appears on the left or right in the operation as follows:
SIDE = aqLaq or aqlaq C := alpha*A*B + beta*C,
SIDE = aqRaq or aqraq C := alpha*B*A + beta*C,
Unchanged on exit.
 UPLO  CHARACTER*1.

On entry, UPLO specifies whether the upper or lower
triangular part of the symmetric matrix A is to be
referenced as follows:
UPLO = aqUaq or aquaq Only the upper triangular part of the symmetric matrix is to be referenced.
UPLO = aqLaq or aqlaq Only the lower triangular part of the symmetric matrix is to be referenced.
Unchanged on exit.
 M  INTEGER.
 On entry, M specifies the number of rows 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 C. N must be at least zero. Unchanged on exit.
 ALPHA  DOUBLE PRECISION.
 On entry, ALPHA specifies the scalar alpha. Unchanged on exit.
 A  DOUBLE PRECISION array of DIMENSION ( LDA, ka ), where ka is
 m when SIDE = aqLaq or aqlaq and is n otherwise. Before entry with SIDE = aqLaq or aqlaq, the m by m part of the array A must contain the symmetric matrix, such that when UPLO = aqUaq or aquaq, the leading m by m upper triangular part of the array A must contain the upper triangular part of the symmetric matrix and the strictly lower triangular part of A is not referenced, and when UPLO = aqLaq or aqlaq, the leading m by m lower triangular part of the array A must contain the lower triangular part of the symmetric matrix and the strictly upper triangular part of A is not referenced. Before entry with SIDE = aqRaq or aqraq, the n by n part of the array A must contain the symmetric matrix, such that when UPLO = aqUaq or aquaq, the leading n by n upper triangular part of the array A must contain the upper triangular part of the symmetric matrix and the strictly lower triangular part of A is not referenced, and when UPLO = aqLaq or aqlaq, the leading n by n lower triangular part of the array A must contain the lower triangular part of the symmetric matrix and the strictly upper triangular part of A is not referenced. Unchanged on exit.
 LDA  INTEGER.
 On entry, LDA specifies the first dimension of A as declared in the calling (sub) program. When SIDE = aqLaq or aqlaq then LDA must be at least max( 1, m ), otherwise LDA must be at least max( 1, n ). Unchanged on exit.
 B  DOUBLE PRECISION array of DIMENSION ( LDB, n ).
 Before entry, the leading m by n 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. LDB must be at least max( 1, m ). Unchanged on exit.
 BETA  DOUBLE PRECISION.
 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  DOUBLE PRECISION 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 updated matrix.
 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.
FURTHER DETAILS
Level 3 Blas routine.
 Written on 8February1989.
Jack Dongarra, Argonne National Laboratory.
Iain Duff, AERE Harwell.
Jeremy Du Croz, Numerical Algorithms Group Ltd.
Sven Hammarling, Numerical Algorithms Group Ltd.