%--------------------------
 % @Author: Jingqiao Hu
 % @Date: 2021-09-18 14:13:07
 % @LastEditTime: 2021-09-18 14:59:44
%--------------------------
function dF = update_dF(edofMat_mi, eleNum_ma, n, dNh_e)
    eleNum_mi = size(edofMat_mi, 1);
    I = eye(eleNum_mi);
    
    initF = repmat([1;0;0;1], 1, eleNum_mi);
    dF = cell(4, eleNum_ma);
    
    tmp_edof = edofMat_mi';
    
    for gp = 1:4
        dNh_g = dNh_e{gp};      % 4*8  
        dNh1  = kron(I, dNh_g); % [4m, 8m]

        for ele = 1:eleNum_ma   
            ne = n{ele};
            n1 = ne(:, tmp_edof(:))'; % [8m, 2v]
            dNH = dNh1 * n1;          % [4m, 2v] 

            % reshape dNH to [4,2v,m]
            dN1 = reshape(dNH, 4, eleNum_mi, []); % [4,m,2v]
            dF{gp, ele} = permute(dN1, [1,3,2]);  % [4,2v,m]
        end
    end
end