csyr.f3
Usage
Functions/Subroutines
subroutine csyr (uplo, n, alpha, x, incx, a, lda)
CSYR performs the symmetric rank-1 update of a complex symmetric matrix.
Function/Subroutine Documentation
subroutine csyr (character uplo, integer n, complex alpha, complex, dimension( * ) x, integer incx, complex, dimension( lda, * ) a, integer lda)
CSYR performs the symmetric rank-1 update of a complex symmetric matrix.
Purpose:
!> !> CSYR performs the symmetric rank 1 operation !> !> A := alpha*x*x**H + A, !> !> where alpha is a complex scalar, x is an n element vector 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. !> !> Unchanged on exit. !>
N
!> N is INTEGER !> On entry, N specifies the order of the matrix A. !> N must be at least zero. !> Unchanged on exit. !>
ALPHA
!> ALPHA is COMPLEX !> On entry, ALPHA specifies the scalar alpha. !> Unchanged on exit. !>
X
!> X is COMPLEX array, dimension at least !> ( 1 + ( N - 1 )*abs( INCX ) ). !> Before entry, the incremented array X must contain the N- !> element vector x. !> Unchanged on exit. !>
INCX
!> INCX is INTEGER !> On entry, INCX specifies the increment for the elements of !> X. INCX must not be zero. !> Unchanged on exit. !>
A
!> A is COMPLEX 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. On exit, the !> upper triangular part of the array A is overwritten by the !> upper triangular part of the updated matrix. !> 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. On exit, the !> lower triangular part of the array A is overwritten by the !> lower triangular part of the updated matrix. !>
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 ). !> Unchanged on exit. !>
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Definition at line 134 of file csyr.f.
Releases
4 releases since Debian 7 (Wheezy); the text changed 3 times.