tut02-page04-example2.cc (flens/examples/tut02-page04-example2.cc)

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#include <cxxstd/iostream.h>

#include <flens/flens.cxx>

using namespace flens;

using namespace std;

int

main()

{

    typedef double                               T;

    typedef DenseVector<Array<T> >               DEVector;

    typedef GeMatrix<FullStorage<T, ColMajor> >  GEMatrix;

    DEVector x(3), y(3), z(3);

    x = 1, 2, 3;

    y = 2, 3, 4;

    z = 3, 4, 5;

    GEMatrix A(3,3);

    A = 1, 2, 3,

        5, 6, 7,

        5, 4, 3;

    ///

    /// We turn on logging of the closure evaluation, i.e. the evaluation

    /// of linear algebra expressions that are coded through overloaded

    /// operators.

    ///

    verbose::ClosureLog::start("mylogfile");

    ///

    /// Compute $v = x + (y + z)$ note that this *must not* be evaluated

    /// as $v = (x + y) + z

    ///

    DEVector v = x + (y + z);

    ///

    /// Compute $z = A (x + y)$ note that this *must not* be evaluated

    /// as $z = Ax + Ay$.

    ///

    z = A*(x+y);

    cout << "x = " << x << endl;

    ///

    /// Stop logging.

    ///

    verbose::ClosureLog::stop();

    return 0;

}