Prototype

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

gebal( const char job, MatrixA& a, int_t& ilo,
        int_t& ihi, VectorSCALE& scale );

Description

gebal (short for $FRIENDLY_NAME) provides a C++ interface to LAPACK routines SGEBAL, DGEBAL, CGEBAL, and ZGEBAL. gebal balances a general complex matrix A. This involves, first, permuting A by a similarity transformation to isolate eigenvalues in the first 1 to ILO-1 and last IHI+1 to N elements on the diagonal; and second, applying a diagonal similarity transformation to rows and columns ILO to IHI to make the rows and columns as close in norm as possible. Both steps are optional.

Balancing may reduce the 1-norm of the matrix, and improve the accuracy of the computed eigenvalues and/or eigenvectors.

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.

Definition

Defined in header boost/numeric/bindings/lapack/computational/gebal.hpp.

Parameters or Requirements on Types

Complexity

Example

#include <boost/numeric/bindings/lapack/computational/gebal.hpp>
using namespace boost::numeric::bindings;

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

this will output

[5] 0 1 2 3 4 5

Notes

See Also