%--------------------------
 % @Author: Jingqiao Hu
 % @Date: 2021-11-26 09:23:33
 % @LastEditTime: 2021-11-28 11:35:00

 % dK is dK_dx_micro
 % dofs is 64 for quad-element, 36 for tr-element
%--------------------------
function [K] = assemble_micro_k(dofid, rho_e, e0, e1, penal, ke, iK, jK, dofs)
    
    new_iK = dofid(iK);
    new_jK = dofid(jK);
    
    nele = size(material(:), 1);
    sK = reshape(ke(:) * (e0 + rho_e(:)'.^penal * (e1 - e0)), dofs * nele, 1);

    K = sparse(new_iK, new_jK, sK(:)); 
    K = (K + K') / 2;
end