Contents
cher2 - perform the hermitian rank 2 operation A :=
alpha*x*conjg( y' ) + conjg( alpha )*y*conjg( x' ) + A
SUBROUTINE CHER2(UPLO, N, ALPHA, X, INCX, Y, INCY, A, LDA)
CHARACTER * 1 UPLO
COMPLEX ALPHA
COMPLEX X(*), Y(*), A(LDA,*)
INTEGER N, INCX, INCY, LDA
SUBROUTINE CHER2_64(UPLO, N, ALPHA, X, INCX, Y, INCY, A, LDA)
CHARACTER * 1 UPLO
COMPLEX ALPHA
COMPLEX X(*), Y(*), A(LDA,*)
INTEGER*8 N, INCX, INCY, LDA
F95 INTERFACE
SUBROUTINE HER2(UPLO, [N], ALPHA, X, [INCX], Y, [INCY], A, [LDA])
CHARACTER(LEN=1) :: UPLO
COMPLEX :: ALPHA
COMPLEX, DIMENSION(:) :: X, Y
COMPLEX, DIMENSION(:,:) :: A
INTEGER :: N, INCX, INCY, LDA
SUBROUTINE HER2_64(UPLO, [N], ALPHA, X, [INCX], Y, [INCY], A, [LDA])
CHARACTER(LEN=1) :: UPLO
COMPLEX :: ALPHA
COMPLEX, DIMENSION(:) :: X, Y
COMPLEX, DIMENSION(:,:) :: A
INTEGER(8) :: N, INCX, INCY, LDA
C INTERFACE
#include <sunperf.h>
void cher2(char uplo, int n, complex *alpha, complex *x, int
incx, complex *y, int incy, complex *a, int lda);
void cher2_64(char uplo, long n, complex *alpha, complex *x,
long incx, complex *y, long incy, complex *a, long
lda);
cher2 performs the hermitian rank 2 operation A :=
alpha*x*conjg( y' ) + conjg( alpha )*y*conjg( x' ) + A where
alpha is a scalar, x and y are n element vectors and A is an
n by n hermitian matrix.
UPLO (input)
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 (input)
On entry, N specifies the order of the matrix A.
N >= 0. Unchanged on exit.
ALPHA (input)
On entry, ALPHA specifies the scalar alpha.
Unchanged on exit.
X (input)
( 1 + ( n - 1 )*abs( INCX ) ). Before entry, the
incremented array X must contain the n element
vector x. Unchanged on exit.
INCX (input)
On entry, INCX specifies the increment for the
elements of X. INCX <> 0. Unchanged on exit.
Y (input)
( 1 + ( n - 1 )*abs( INCY ) ). Before entry, the
incremented array Y must contain the n element
vector y. Unchanged on exit.
INCY (input)
On entry, INCY specifies the increment for the
elements of Y. INCY <> 0. Unchanged on exit.
A (input/output)
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 hermitian
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 hermitian 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. Note that the ima-
ginary parts of the diagonal elements need not be
set, they are assumed to be zero, and on exit they
are set to zero.
LDA (input)
On entry, LDA specifies the first dimension of A
as declared in the calling (sub) program. LDA >=
max( 1, n ). Unchanged on exit.