偏微分演算子の座標変換

$ \frac{\partial\bullet}{\partial e_i}=\sum_j\frac{\partial\bullet}{\partial f_j}\frac{\partial f_j}{\partial e_i}=\sum_j[\pmb{I}]^\mathsf{\bar{E}F}_{ij}\frac{\partial\bullet}{\partial f_j}

$ \therefore \frac{\partial\bullet}{\partial e_i}=\sum_j[\pmb{I}]^\mathsf{\bar{E}F}_{ij}\frac{\partial\bullet}{\partial f_j}