Function GetGradient

fem/shapefunction_utils.hpp:12–18

  // for shape functions 
  template <int DIM, typename SCAL>
  auto GetGradient (const AutoDiff<DIM,SCAL> & ad)
  {
    Vec<DIM,SCAL> grad;
    for (int i = 0; i < DIM; i++)
      grad(i) = ad.DValue(i);
    return grad;
  }