BLAS/SRC/ssymv.f(3) Library Functions Manual BLAS/SRC/ssymv.f(3) NAME BLAS/SRC/ssymv.f SYNOPSIS Functions/Subroutines subroutine ssymv (uplo, n, alpha, a, lda, x, incx, beta, y, incy) SSYMV Function/Subroutine Documentation subroutine ssymv (character uplo, integer n, real alpha, real, dimension(lda,*) a, integer lda, real, dimension(*) x, integer incx, real beta, real, dimension(*) y, integer incy) SSYMV Purpose: !> !> SSYMV performs the matrix-vector operation !> !> y := alpha*A*x + beta*y, !> !> where alpha and beta are scalars, x and y are n element vectors and !> A is an n by n symmetric matrix. !> Parameters UPLO !> UPLO is CHARACTER*1 !> On entry, UPLO specifies whether the upper or lower !> triangular part of the array A is to be referenced as !> follows: !> !> UPLO = 'U' or 'u' Only the upper triangular part of A !> is to be referenced. !> !> UPLO = 'L' or 'l' Only the lower triangular part of A !> is to be referenced. !> N !> N is INTEGER !> On entry, N specifies the order of the matrix A. !> N must be at least zero. !> ALPHA !> ALPHA is REAL !> On entry, ALPHA specifies the scalar alpha. !> A !> A is REAL array, dimension ( LDA, N ) !> Before entry with 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. !> Before entry with 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. !> LDA !> LDA is INTEGER !> On entry, LDA specifies the first dimension of A as declared !> in the calling (sub) program. LDA must be at least !> max( 1, n ). !> X !> X is REAL array, dimension at least !> ( 1 + ( n - 1 )*abs( INCX ) ). !> Before entry, the incremented array X must contain the n !> element vector x. !> INCX !> INCX is INTEGER !> On entry, INCX specifies the increment for the elements of !> X. INCX must not be zero. !> BETA !> BETA is REAL !> On entry, BETA specifies the scalar beta. When BETA is !> supplied as zero then Y need not be set on input. !> Y !> Y is REAL array, dimension at least !> ( 1 + ( n - 1 )*abs( INCY ) ). !> Before entry, the incremented array Y must contain the n !> element vector y. On exit, Y is overwritten by the updated !> vector y. !> INCY !> INCY is INTEGER !> On entry, INCY specifies the increment for the elements of !> Y. INCY must not be zero. !> Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Further Details: !> !> Level 2 Blas routine. !> The vector and matrix arguments are not referenced when N = 0, or M = 0 !> !> -- Written on 22-October-1986. !> Jack Dongarra, Argonne National Lab. !> Jeremy Du Croz, Nag Central Office. !> Sven Hammarling, Nag Central Office. !> Richard Hanson, Sandia National Labs. !> Definition at line 151 of file ssymv.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 BLAS/SRC/ssymv.f(3)