##### ungtr

###### Prototype

There is one prototype of `ungtr` available, please see below.

    ungtr( const int_t n, MatrixA& a, const VectorTAU& tau );

###### Description

`ungtr` (short for $FRIENDLY_NAME) provides a C++ interface to LAPACK routines SORGTR, DORGTR, CUNGTR, and ZUNGTR. `ungtr` generates a complex unitary matrix Q which is defined as the product of n-1 elementary reflectors of order N, as returned by ZHETRD:

if UPLO = 'U', Q = H(n-1) . . . H(2) H(1),

if UPLO = 'L', Q = H(1) H(2) . . . H(n-1).

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 1.326. Dispatching of ungtr

Value type of MatrixA | LAPACK routine
--- | ---
`float` | SORGTR
`double` | DORGTR
`complex<float>` | CUNGTR
`complex<double>` | ZUNGTR

###### Definition

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

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

this will output

    [5] 0 1 2 3 4 5

###### Notes

###### See Also

- Originating Fortran source files sorgtr.f, dorgtr.f, cungtr.f, and zungtr.f at Netlib.