Contents
cherk - perform one of the Hermitian rank k operations C
:= alpha*A*conjg( A' ) + beta*C or C := alpha*conjg( A' )*A
+ beta*C
SUBROUTINE CHERK(UPLO, TRANSA, N, K, ALPHA, A, LDA, BETA, C, LDC)
CHARACTER * 1 UPLO, TRANSA
COMPLEX A(LDA,*), C(LDC,*)
INTEGER N, K, LDA, LDC
REAL ALPHA, BETA
SUBROUTINE CHERK_64(UPLO, TRANSA, N, K, ALPHA, A, LDA, BETA, C, LDC)
CHARACTER * 1 UPLO, TRANSA
COMPLEX A(LDA,*), C(LDC,*)
INTEGER*8 N, K, LDA, LDC
REAL ALPHA, BETA
F95 INTERFACE
SUBROUTINE HERK(UPLO, [TRANSA], [N], [K], ALPHA, A, [LDA], BETA, C,
[LDC])
CHARACTER(LEN=1) :: UPLO, TRANSA
COMPLEX, DIMENSION(:,:) :: A, C
INTEGER :: N, K, LDA, LDC
REAL :: ALPHA, BETA
SUBROUTINE HERK_64(UPLO, [TRANSA], [N], [K], ALPHA, A, [LDA], BETA,
C, [LDC])
CHARACTER(LEN=1) :: UPLO, TRANSA
COMPLEX, DIMENSION(:,:) :: A, C
INTEGER(8) :: N, K, LDA, LDC
REAL :: ALPHA, BETA
C INTERFACE
#include <sunperf.h>
void cherk(char uplo, char transa, int n, int k, float
alpha, complex *a, int lda, float beta, complex
*c, int ldc);
void cherk_64(char uplo, char transa, long n, long k, float
alpha, complex *a, long lda, float beta, complex
*c, long ldc);
cherk performs one of the Hermitian rank k operations C :=
alpha*A*conjg( A' ) + beta*C or C := alpha*conjg( A' )*A +
beta*C where alpha and beta are real scalars, C is an n
by n Hermitian matrix and A is an n by k matrix in the
first case and a k by n matrix in the second case.
UPLO (input)
On entry, UPLO specifies whether the upper
or lower triangular part of the array C is
to be referenced as follows:
UPLO = 'U' or 'u' Only the upper triangular
part of C is to be referenced.
UPLO = 'L' or 'l' Only the lower triangular
part of C is to be referenced.
Unchanged on exit.
TRANSA (input)
On entry, TRANSA specifies the operation to be
performed as follows:
TRANSA = 'N' or 'n' C := alpha*A*conjg( A' ) +
beta*C.
TRANSA = 'C' or 'c' C := alpha*conjg( A' )*A +
beta*C.
Unchanged on exit.
TRANSA is defaulted to 'N' for F95 INTERFACE.
N (input)
On entry, N specifies the order of the matrix C.
N must be at least zero. Unchanged on exit.
K (input)
On entry with TRANSA = 'N' or 'n', K specifies
the number of columns of the matrix A,
and on entry with TRANSA = 'C' or 'c', K
specifies the number of rows of the matrix A. K
must be at least zero. Unchanged on exit.
ALPHA (input)
On entry, ALPHA specifies the scalar alpha.
Unchanged on exit.
A (input)
COMPLEX array of DIMENSION ( LDA, ka ),
where ka is k when TRANSA = 'N' or 'n', and is
n otherwise. Before entry with TRANSA = 'N' or
'n', the leading n by k part of the array A
must contain the matrix A, otherwise the leading
k by n part of the array A must contain the
matrix A. Unchanged on exit.
LDA (input)
On entry, LDA specifies the first dimension of A
as declared in the calling (sub) program.
When TRANSA = 'N' or 'n' then LDA must be at
least max( 1, n ), otherwise LDA must be at
least max( 1, k ). Unchanged on exit.
BETA (input)
On entry, BETA specifies the scalar beta.
Unchanged on exit.
C (input/output)
COMPLEX array of DIMENSION ( LDC, n ).
Before entry with UPLO = 'U' or 'u', the lead-
ing n by n upper triangular part of the array C
must contain the upper triangular part of the
Hermitian matrix and the strictly lower triangu-
lar part of C is not referenced. On exit, the
upper triangular part of the array C is overwrit-
ten by the upper triangular part of the updated
matrix.
Before entry with UPLO = 'L' or 'l', the lead-
ing n by n lower triangular part of the array C
must contain the lower triangular part of the
Hermitian matrix and the strictly upper triangu-
lar part of C is not referenced. On exit, the
lower triangular part of the array C is overwrit-
ten by the lower triangular part of the updated
matrix.
Note that the imaginary parts of the diagonal ele-
ments need not be set, they are assumed to be
zero, and on exit they are set to zero.
LDC (input)
On entry, LDC specifies the first dimension of C
as declared in the calling (sub) program.
LDC must be at least max( 1, n ). Unchanged
on exit.