lapack-getrs.cc (flens/examples/lapack-getrs.cc)

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#include <cxxstd/iostream.h>

#include <flens/flens.cxx>

using namespace std;

using namespace flens;

int

main()

{

    GeMatrix<FullStorage<double> >   A(4, 4);

    DenseVector<Array<double> >      b(4);

    DenseVector<Array<int> >         piv(4);

    A =  2,   3,  -1,   0,

        -6,  -5,   0,   2,

         2,  -5,   6,  -6,

         4,   6,   2,  -3;

    b = 20,

       -33,

       -43,

        49;

    cout << "A = " << A << endl;

    cout << "b = " << b << endl;

///

/// Compute the $PLU = A$ factorization with __lapack::trf__

///

    lapack::trf(A, piv);

///

/// Solve the system of linear equation $PLUx = b$ using __lapack::trs__.

/// Vector $b$ gets overwritten with vector $x$.

///

    lapack::trs(NoTrans, A, piv, b);

    cout << "X = " << b << endl;

}

///

///  :links: __lapack::trf__ -> file:flens/lapack/ge/trf.h

///          __lapack::trs__ -> file:flens/lapack/ge/trs.h

///