Yi=linspace(Ymin,Ymax,30);

[XXi,YYi]=meshgrid(Xi,Yi);

Zi=griddata(X,Y,z,XXi,YYi);

[c1,h]=contour(XXi,YYi,Zi);

clabel(c1,h);

zi=griddata(X,Y,Zz,XXi,YYi);

[c2,h]=contour(XXi,YYi,zi);

clabel(c2,h)