herk

Prototype

There is one prototype of herk available, please see below.

herk( const Scalar >, const MatrixA& a, const Scalar >, MatrixC& c );

Description

herk (short for hermitian rank-k update) provides a C++ interface to BLAS routines SSYRK, DSYRK, CHERK, and ZHERK. herk performs one of the hermitian rank k operations

C := alpha*A*conjg( A' ) + beta*C,

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.

The selection of the BLAS routine is done during compile-time, and is determined by the type of values contained in type MatrixA. The type of values is obtained through the value_type meta-function typename value_type<MatrixA>::type. Table X below illustrates to which specific routine this dispatching will take place.

Table 1.88. Dispatching of herk.

Value type of MatrixA	BLAS routine	CBLAS routine	CUBLAS routine
`float`	SSYRK	cblas_ssyrk	cublasSsyrk
`double`	DSYRK	cblas_dsyrk	cublasDsyrk
`complex<float>`	CHERK	cblas_cherk	cublasCherk
`complex<double>`	ZHERK	cblas_zherk	Unavailable

The original routines SSYRK, DSYRK, CHERK, and ZHERK have ten arguments, whereas herk requires four arguments.

Table 1.89. Deduction of arguments of herk.

Definition

Defined in header boost/numeric/bindings/blas/level3/herk.hpp.

Parameters or Requirements on Types

Parameters

MatrixA

The definition of term 1

MatrixB

The definition of term 2

MatrixC

The definition of term 3.

Definitions may contain paragraphs.

Complexity

Example

#include <boost/numeric/bindings/blas/level3/herk.hpp>
using namespace boost::numeric::bindings;

blas::herk( x, y, z );

this will output

[5] 0 1 2 3 4 5