final BoundaryCondition lower = new NeumannBoundaryCondition(0.0, grid.getSpaceNode(0), true);
//BoundaryCondition lower = new DirichletBoundaryCondition(0.0, grid.getSpaceNode(0));//TODO for beta < 0.5 zero is accessible and thus there will be non-zero
//density there
final BoundaryCondition upper = new DirichletBoundaryCondition(0.0, grid.getSpaceNode(grid.getNumSpaceNodes() - 1));
CoupledPDEDataBundle d1 = new CoupledPDEDataBundle(_data1, _initCon11, lower, upper, grid);
CoupledPDEDataBundle d2 = new CoupledPDEDataBundle(_data2, _initCon12, lower, upper, grid);
final CoupledFiniteDifference solver = new CoupledFiniteDifference(THETA, true);
final PDEResults1D[] res = solver.solve(d1, d2);
//handle this with generics
final PDEFullResults1D res1 = (PDEFullResults1D) res[0];