www.gusucode.com > 界面看成高一维空间中某一函数ψ源码程序 > levelsetcode/BoundMirrorExpand.m

    function B = BoundMirrorExpand(A)

[m,n] = size(A);
yi = 2:m+1;
xi = 2:n+1;
B = zeros(m+2,n+2);
B(yi,xi) = A;
B([1 m+2],[1 n+2]) = B([3 m],[3 n]);  % mirror corners
B([1 m+2],xi) = B([3 m],xi);          % mirror left and right boundary
B(yi,[1 n+2]) = B(yi,[3 n]);          % mirror top and bottom boundary