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poequ
Prototype

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

poequ( const MatrixA& a, VectorS& s, Scalar >, Scalar > );

Description

poequ (short for $FRIENDLY_NAME) provides a C++ interface to LAPACK routines SPOEQU, DPOEQU, CPOEQU, and ZPOEQU. poequ computes row and column scalings intended to equilibrate a Hermitian positive definite matrix A and reduce its condition number (with respect to the two-norm). S contains the scale factors, S(i) = 1/sqrt(A(i,i)), chosen so that the scaled matrix B with elements B(i,j) = S(i)*A(i,j)*S(j) has ones on the diagonal. This choice of S puts the condition number of B within a factor N of the smallest possible condition number over all possible diagonal scalings.

The selection of the LAPACK 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. The dispatching table below illustrates to which specific routine the code path will be generated.

Table 1.270. Dispatching of poequ

Value type of MatrixA

LAPACK routine

float

SPOEQU

double

DPOEQU

complex<float>

CPOEQU

complex<double>

ZPOEQU


Definition

Defined in header boost/numeric/bindings/lapack/computational/poequ.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/lapack/computational/poequ.hpp>
using namespace boost::numeric::bindings;

lapack::poequ( x, y, z );

this will output

[5] 0 1 2 3 4 5

Notes
See Also

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