lapack-complex-getrf.cc (flens/examples/lapack-complex-getrf.cc)

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#include <cxxstd/iostream.h>

#include <flens/flens.cxx>

using namespace std;

using namespace flens;

typedef complex<double>   T;

int

main()

{

    typedef GeMatrix<FullStorage<T> >           Matrix;

    typedef Matrix::IndexType                   IndexType;

    typedef DenseVector<Array<IndexType> >      IndexVector;

    const Underscore<IndexType> _;

    ///

    ///  Set up the baby problem ...

    ///

    const IndexType m = 4,

                    n = 5;

    Matrix            Ab(m, n);

    IndexVector       piv(m);

    Ab = T(1, 0), T( 1,-1), T(  2,20), T( 1, 0),

         T(0, 1), T( 1, 2), T(-10, 8), T(-1, 1),

         T(0,-1), T(-1, 1), T( 40, 6), T(-2,-1);

    cout << "Ab = " << Ab << endl;

    ///

    /// Compute the $LU$ factorization with __lapack::trf__

    ///

    lapack::trf(Ab, piv);

    ///

    ///  Solve the system of linear equation $Ax =B$ using __blas::sm__

    ///

    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;

    cout << "piv = " << piv << endl;

}

///

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

///          __blas::sm__ -> file:flens/blas/level3/sm.h

///