mpfr-real-lapack-getrf.cc (flens/examples/mpfr-real-lapack-getrf.cc)

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#include <cxxstd/iostream.h>

///

/// Include header file for `mpfr::real` before `flens.cxx` and make

/// sure that conversion operators are enabled

///

#define REAL_ENABLE_CONVERSION_OPERATORS

#include <external/real.hpp>

#include <flens/flens.cxx>

using namespace std;

using namespace flens;

///

///  Make typedef for using mpfr::real

///

typedef mpfr::real<53>   T;

int

main()

{

    typedef GeMatrix<FullStorage<T> >           Matrix;

    typedef DenseVector<Array<T> >              Vector;

    typedef Matrix::IndexType                   IndexType;

    typedef DenseVector<Array<IndexType> >      IndexVector;

    const Underscore<IndexType> _;

    const IndexType m = 4,

                    n = 5;

    Matrix            Ab(m, n);

    IndexVector       piv(m);

    Ab =  2,   3,  -1,   0,  20,

         -6,  -5,   0,   2, -33,

          2,  -5,   6,  -6, -43,

          4,   6,   2,  -3,  49;

    cout << "Ab = " << Ab << endl;

    lapack::trf(Ab, piv);

    const auto A = Ab(_,_(1,m));

    auto       B = Ab(_,_(m+1,n));

    blas::sm(Left, NoTrans, T(1), A.upper(), B);

    cout << "X = " << B << endl;

}