There are two prototypes of ptrfs
            available, please see below. 
ptrfs( const VectorD& d, const VectorE& e, const VectorDF& df, const VectorEF& ef, const MatrixB& b, MatrixX& x, VectorFERR& ferr, VectorBERR& berr );
ptrfs( const char uplo, const VectorD& d, const VectorE& e, const VectorDF& df, const VectorEF& ef, const MatrixB& b, MatrixX& x, VectorFERR& ferr, VectorBERR& berr );
            ptrfs (short for $FRIENDLY_NAME)
            provides a C++ interface to LAPACK routines SPTRFS, DPTRFS, CPTRFS, and
            ZPTRFS. ptrfs improves
            the computed solution to a system of linear equations when the coefficient
            matrix is Hermitian positive definite and tridiagonal, and provides error
            bounds and backward error estimates for the solution.
          
            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.
          
Table 1.283. Dispatching of ptrfs
| Value type of VectorD | LAPACK routine | 
|---|---|
| 
                       | SPTRFS | 
| 
                       | DPTRFS | 
| 
                       | CPTRFS | 
| 
                       | ZPTRFS | 
            Defined in header boost/numeric/bindings/lapack/computational/ptrfs.hpp.
          
Parameters
The definition of term 1
The definition of term 2
The definition of term 3.
Definitions may contain paragraphs.
#include <boost/numeric/bindings/lapack/computational/ptrfs.hpp> using namespace boost::numeric::bindings; lapack::ptrfs( x, y, z );
this will output
[5] 0 1 2 3 4 5