ssymm (l) - Linux Manuals
ssymm: performs one of the matrix-matrix operations C := alpha*A*B + beta*C,
Command to display ssymm
manual in Linux: $ man l ssymm
NAME
SSYMM - performs one of the matrix-matrix operations C := alpha*A*B + beta*C,
SYNOPSIS
- SUBROUTINE SSYMM(SIDE,UPLO,M,N,ALPHA,A,LDA,B,LDB,BETA,C,LDC)
-
-
REAL
ALPHA,BETA
-
INTEGER
LDA,LDB,LDC,M,N
-
CHARACTER
SIDE,UPLO
-
REAL
A(LDA,*),B(LDB,*),C(LDC,*)
PURPOSE
SSYMM performs one of the matrix-matrix operations
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 - 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 - REAL .
-
On entry, ALPHA specifies the scalar alpha.
Unchanged on exit.
- A - REAL 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 - REAL 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 - REAL .
-
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 - REAL 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 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.
Pages related to ssymm
- ssymm (3)
- ssymv (l) - performs the matrix-vector operation y := alpha*A*x + beta*y,
- ssycon (l) - estimates the reciprocal of the condition number (in the 1-norm) of a real symmetric matrix A using the factorization A = U*D*U**T or A = L*D*L**T computed by SSYTRF
- ssyequb (l) - computes row and column scalings intended to equilibrate a symmetric matrix A and reduce its condition number (with respect to the two-norm)
- ssyev (l) - computes all eigenvalues and, optionally, eigenvectors of a real symmetric matrix A
- ssyevd (l) - computes all eigenvalues and, optionally, eigenvectors of a real symmetric matrix A
- ssyevr (l) - computes selected eigenvalues and, optionally, eigenvectors of a real symmetric matrix A
- ssyevx (l) - computes selected eigenvalues and, optionally, eigenvectors of a real symmetric matrix A
- ssygs2 (l) - reduces a real symmetric-definite generalized eigenproblem to standard form