##### gelss

###### Prototype

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

    gelss( MatrixA& a, MatrixB& b, VectorS& s, const Scalar >,
            int_t& rank );

###### Description

`gelss` (short for $FRIENDLY_NAME) provides a C++ interface to LAPACK routines SGELSS, DGELSS, CGELSS, and ZGELSS. `gelss` computes the minimum norm solution to a complex linear least squares problem:

Minimize 2-norm(| b - A*x |).

using the singular value decomposition (SVD) of A. A is an M-by-N matrix which may be rank-deficient.

Several right hand side vectors b and solution vectors x can be handled in a single call; they are stored as the columns of the M-by-NRHS right hand side matrix B and the N-by-NRHS solution matrix X.

The effective rank of A is determined by treating as zero those singular values which are less than RCOND times the largest singular value.

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 1.183. Dispatching of gelss

Value type of MatrixA | LAPACK routine
--- | ---
`float` | SGELSS
`double` | DGELSS
`complex<float>` | CGELSS
`complex<double>` | ZGELSS

###### Definition

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

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

this will output

    [5] 0 1 2 3 4 5

###### Notes

###### See Also

- Originating Fortran source files sgelss.f, dgelss.f, cgelss.f, and zgelss.f at Netlib.