function R=MakeRegmatrix(Element);%MakeRegmatrix Computes a regularisation matrix which includes smoothness assumptions% Function R=MakeRegmatrix(Element);% computes a regularization matrix R which is a version of 2D difference. %% INPUT% Element = element structure%% OUTPUT% R = regularisation matrixmsE=max(size(Element)); %剖分1的單元數(shù)R=sparse(msE,msE);      %重構(gòu)稀疏矩陣Rfor ii=1:msE Inds=[Element(ii).Face{:,2}]; R(ii,Inds(Inds~=0))=-1; R(ii,ii)=abs(sum(R(ii,:)));end