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];
final PDEFullResults1D res2 = (PDEFullResults1D) res[1];
return new PDEFullResults1D[] {res1, res2 };
}