zher2k(3P) Sun Performance Library zher2k(3P)NAMEzher2k - perform one of the Hermitian rank 2k operations C :=
alpha*A*conjg( B' ) + conjg( alpha )*B*conjg( A' ) + beta*C or C :=
alpha*conjg( A' )*B + conjg( alpha )*conjg( B' )*A + beta*C
SYNOPSIS
SUBROUTINE ZHER2K(UPLO, TRANSA, N, K, ALPHA, A, LDA, B, LDB, BETA, C,
LDC)
CHARACTER * 1 UPLO, TRANSA
DOUBLE COMPLEX ALPHA
DOUBLE COMPLEX A(LDA,*), B(LDB,*), C(LDC,*)
INTEGER N, K, LDA, LDB, LDC
DOUBLE PRECISION BETA
SUBROUTINE ZHER2K_64(UPLO, TRANSA, N, K, ALPHA, A, LDA, B, LDB, BETA,
C, LDC)
CHARACTER * 1 UPLO, TRANSA
DOUBLE COMPLEX ALPHA
DOUBLE COMPLEX A(LDA,*), B(LDB,*), C(LDC,*)
INTEGER*8 N, K, LDA, LDB, LDC
DOUBLE PRECISION BETA
F95 INTERFACE
SUBROUTINE HER2K(UPLO, [TRANSA], [N], [K], ALPHA, A, [LDA], B, [LDB],
BETA, C, [LDC])
CHARACTER(LEN=1) :: UPLO, TRANSA
COMPLEX(8) :: ALPHA
COMPLEX(8), DIMENSION(:,:) :: A, B, C
INTEGER :: N, K, LDA, LDB, LDC
REAL(8) :: BETA
SUBROUTINE HER2K_64(UPLO, [TRANSA], [N], [K], ALPHA, A, [LDA], B,
[LDB], BETA, C, [LDC])
CHARACTER(LEN=1) :: UPLO, TRANSA
COMPLEX(8) :: ALPHA
COMPLEX(8), DIMENSION(:,:) :: A, B, C
INTEGER(8) :: N, K, LDA, LDB, LDC
REAL(8) :: BETA
C INTERFACE
#include <sunperf.h>
void zher2k(char uplo, char transa, int n, int k, doublecomplex *alpha,
doublecomplex *a, int lda, doublecomplex *b, int ldb, double
beta, doublecomplex *c, int ldc);
void zher2k_64(char uplo, char transa, long n, long k, doublecomplex
*alpha, doublecomplex *a, long lda, doublecomplex *b, long
ldb, double beta, doublecomplex *c, long ldc);
PURPOSEzher2k performs one of the Hermitian rank 2k operations C :=
alpha*A*conjg( B' ) + conjg( alpha )*B*conjg( A' ) + beta*C or C :=
alpha*conjg( A' )*B + conjg( alpha )*conjg( B' )*A + beta*C where
alpha and beta are scalars with beta real, C is an n by n Hermit‐
ian matrix and A and B are n by k matrices in the first case and k
by n matrices in the second case.
ARGUMENTS
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( B' ) +
conjg( alpha )*B*conjg( A' ) + beta*C.
TRANSA = 'C' or 'c' C := alpha*conjg( A' )*B +
conjg( alpha )*conjg( B' )*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 matrices A and B, and on entry with
TRANSA = 'C' or 'c', K specifies the number of rows of the
matrices A and B. K must be at least zero. Unchanged on
exit.
ALPHA (input)
On entry, ALPHA specifies the scalar alpha. Unchanged on
exit.
A (input)
COMPLEX*16 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.
B (input)
COMPLEX*16 array of DIMENSION ( LDB, kb ), where kb 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 B must contain the matrix B, otherwise the
leading k by n part of the array B must contain the
matrix B. Unchanged on exit.
LDB (input)
On entry, LDB specifies the first dimension of B as declared
in the calling (sub) program. When TRANSA = 'N' or 'n'
then LDB must be at least max( 1, n ), otherwise LDB 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*16 array of DIMENSION ( LDC, n ).
Before entry with UPLO = 'U' or 'u', the leading n by n
upper triangular part of the array C must contain the upper
triangular part of the Hermitian matrix and the strictly
lower triangular part of C is not referenced. On exit, the
upper triangular part of the array C 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 C must contain the lower
triangular part of the Hermitian matrix and the strictly
upper triangular part of C is not referenced. On exit, the
lower triangular part of the array C is overwritten by the
lower triangular part of the updated matrix.
Note that the imaginary parts of the diagonal elements 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.
6 Mar 2009 zher2k(3P)
