##### trmv

###### Prototype

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

    trmv( const MatrixA& a, VectorX& x );

###### Description

`trmv` (short for triangular matrix-vector operation) provides a C++ interface to BLAS routines STRMV, DTRMV, CTRMV, and ZTRMV. `trmv` performs one of the matrix-vector operations

x := A*x, or x := A'*x, or x := conjg( A' )*x,

where x is an n element vector and A is an n by n unit, or non-unit, upper or lower triangular matrix.

The selection of the BLAS 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`. Table X below illustrates to which specific routine this dispatching will take place.

Table 1.78. Dispatching of trmv.

Value type of MatrixA | BLAS routine | CBLAS routine | CUBLAS routine
--- | --- | --- | ---
`float` | STRMV | cblas_strmv | cublasStrmv
`double` | DTRMV | cblas_dtrmv | Unavailable
`complex<float>` | CTRMV | cblas_ctrmv | Unavailable
`complex<double>` | ZTRMV | cblas_ztrmv | Unavailable

The original routines STRMV, DTRMV, CTRMV, and ZTRMV have eight arguments, whereas `trmv` requires two arguments.

Table 1.79. Deduction of arguments of trmv.

###### Definition

Defined in header `boost/numeric/bindings/blas/level2/trmv.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/blas/level2/trmv.hpp>
    using namespace boost::numeric::bindings;

    blas::trmv( x, y, z );

this will output

    [5] 0 1 2 3 4 5

###### Notes

###### See Also

- Originating Fortran source files strmv.f, dtrmv.f, ctrmv.f, and ztrmv.f at Netlib.