Method DiffJacobi

fem/coefficient_matrix.cpp:639–664

    }

    shared_ptr<CoefficientFunction>
    DiffJacobi (const CoefficientFunction * var, typename BASE::T_DJC & cache) const override
    {
      auto thisptr = const_pointer_cast<CoefficientFunction>(this->shared_from_this());
      if (cache.find(thisptr) != cache.end())
        return cache[thisptr];

      if (this == var) return make_shared<ConstantCoefficientFunction>(1);
      if (c1.get() == var) return CofactorCF (c1);
      auto input = c1->InputCoefficientFunctions();
      if (input.Size() == 0) return ZeroCF(var->Dimensions());

      auto cof = CofactorCF(c1) -> Reshape( 1, D*D );
      auto diffc1 = c1->DiffJacobi (var, cache) -> Reshape( D*D, var->Dimension() );
      auto prod = cof * diffc1;
      auto res = prod->Reshape(var->Dimensions());

      /*
        auto cof = CofactorCF(c1) -> Reshape( D*D );
        auto diffc1 = c1->DiffJacobi (var, cache) -> Reshape( D*D, var->Dimension() );
        auto res = diffc1->Transpose() * cof;
      */
    
      cache[thisptr] = res;
      return res;
    }

  
  };