testproblem6.h

Dolfin provide a high-performance linear algebra library

// Copyright (C) 2004-2006 Anders Logg.
// Licensed under the GNU LGPL Version 2.1.
//
// First added:  2004
// Last changed: 2006-08-21

#include <cmath>
#include <dolfin.h>

using namespace dolfin;

class TestProblem6 : public ODE
{
public:
  
  TestProblem6() : ODE(2, 100.0)
  {
    message("Van der Pol's equation.");

    mu = 10.0;
  }

  void u0(uBlasVector& u)
  {
    u(0) = 2.0;
    u(1) = 0.0;
  }

  void f(const uBlasVector& u, real t, uBlasVector& y)
  {
    y(0) = u(1);
    y(1) = mu*(1.0 - u(0)*u(0))*u(1) - u(0);
  }

private:

  real mu;

};