dsymm


NAME

dsymm - perform one of the matrix-matrix operations C := alpha*A*B + beta*C or C := alpha*B*A + beta*C


SYNOPSIS

  SUBROUTINE DSYMM( SIDE, UPLO, M, N, ALPHA, A, LDA, B, LDB, BETA, C, 
 *      LDC)
  CHARACTER * 1 SIDE, UPLO
  INTEGER M, N, LDA, LDB, LDC
  DOUBLE PRECISION ALPHA, BETA
  DOUBLE PRECISION A(LDA,*), B(LDB,*), C(LDC,*)
 
  SUBROUTINE DSYMM_64( SIDE, UPLO, M, N, ALPHA, A, LDA, B, LDB, BETA, 
 *      C, LDC)
  CHARACTER * 1 SIDE, UPLO
  INTEGER*8 M, N, LDA, LDB, LDC
  DOUBLE PRECISION ALPHA, BETA
  DOUBLE PRECISION A(LDA,*), B(LDB,*), C(LDC,*)
 

F95 INTERFACE

  SUBROUTINE SYMM( SIDE, UPLO, [M], [N], ALPHA, A, [LDA], B, [LDB], 
 *       BETA, C, [LDC])
  CHARACTER(LEN=1) :: SIDE, UPLO
  INTEGER :: M, N, LDA, LDB, LDC
  REAL(8) :: ALPHA, BETA
  REAL(8), DIMENSION(:,:) :: A, B, C
 
  SUBROUTINE SYMM_64( SIDE, UPLO, [M], [N], ALPHA, A, [LDA], B, [LDB], 
 *       BETA, C, [LDC])
  CHARACTER(LEN=1) :: SIDE, UPLO
  INTEGER(8) :: M, N, LDA, LDB, LDC
  REAL(8) :: ALPHA, BETA
  REAL(8), DIMENSION(:,:) :: A, B, C
 

C INTERFACE

#include <sunperf.h>

void dsymm(char side, char uplo, int m, int n, double alpha, double *a, int lda, double *b, int ldb, double beta, double *c, int ldc);

void dsymm_64(char side, char uplo, long m, long n, double alpha, double *a, long lda, double *b, long ldb, double beta, double *c, long ldc);


PURPOSE

dsymm performs one of the matrix-matrix operations C := alpha*A*B + beta*C or C := alpha*B*A + beta*C where alpha and beta are scalars, A is a symmetric matrix and B and C are m by n matrices.


ARGUMENTS

* SIDE (input)
On entry, SIDE specifies whether the symmetric matrix A appears on the left or right in the operation as follows:

SIDE = 'L' or 'l' C := alpha*A*B + beta*C,

SIDE = 'R' or 'r' C := alpha*B*A + beta*C,

Unchanged on exit.

* UPLO (input)
On entry, UPLO specifies whether the upper or lower triangular part of the symmetric matrix A is to be referenced as follows:

UPLO = 'U' or 'u' Only the upper triangular part of the symmetric matrix is to be referenced.

UPLO = 'L' or 'l' Only the lower triangular part of the symmetric matrix is to be referenced.

Unchanged on exit.

* M (input)
On entry, M specifies the number of rows of the matrix C. M >= 0. Unchanged on exit.

* N (input)
On entry, N specifies the number of columns of the matrix C. N >= 0. Unchanged on exit.

* ALPHA (input)
On entry, ALPHA specifies the scalar alpha. Unchanged on exit.

* A (input)
m when SIDE = 'L' or 'l' and is n otherwise.

Before entry with SIDE = 'L' or 'l', the m by m part of the array A must contain the symmetric matrix, such that when UPLO = 'U' or 'u', 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 = 'L' or 'l', 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 = 'R' or 'r', the n by n part of the array A must contain the symmetric matrix, such that when UPLO = 'U' or 'u', 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 = 'L' or 'l', 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 (input)
On entry, LDA specifies the first dimension of A as declared in the calling (sub) program. When SIDE = 'L' or 'l' then LDA >= max( 1, m ), otherwise LDA >= max( 1, n ). Unchanged on exit.

* B (input)
Before entry, the leading m by n part of the array B must contain the matrix B. Unchanged on exit.

* LDB (input)
On entry, LDB specifies the first dimension of B as declared in the calling (sub) program. LDB >= max( 1, m ). Unchanged on exit.

* BETA (input)
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 (input/output)
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 (input)
On entry, LDC specifies the first dimension of C as declared in the calling (sub) program. LDC >= max( 1, m ). Unchanged on exit.