Prototype

There are two prototypes of pttrs available, please see below.

pttrs( const VectorD& d, const VectorE& e, MatrixB& b );

pttrs( const char uplo, const VectorD& d, const VectorE& e, MatrixB& b );

Description

pttrs (short for $FRIENDLY_NAME) provides a C++ interface to LAPACK routines SPTTRS, DPTTRS, CPTTRS, and ZPTTRS. pttrs solves a tridiagonal system of the form A * X = B using the factorization A = U'*D*U or A = L*D*L' computed by ZPTTRF. D is a diagonal matrix specified in the vector D, U (or L) is a unit bidiagonal matrix whose superdiagonal (subdiagonal) is specified in the vector E, and X and B are N by NRHS matrices.

The selection of the LAPACK routine is done during compile-time, and is determined by the type of values contained in type VectorD. The type of values is obtained through the value_type meta-function typename value_type<VectorD>::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/pttrs.hpp.

Parameters or Requirements on Types

Complexity

Example

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

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

this will output

[5] 0 1 2 3 4 5

Notes

See Also