山区地貌问题.doc

山区地貌问题：在某山区测得一些地点的高程如下表。（平面区域为：1200=x=4000,1200=y=3600)。试作出该山区的地貌图和等高线图，并对几种插值方法进行比较。解：x0=1200:400:4000;y0=1200:400:3600;z0=1130,1250,1280,1230,1040,900,500,700; 1320,1450,1420,1400,1300,700,900,850; 1390,1500,1500,1400,900,1100,1060,950; 1500,1200,1100,1350,1450,1200,1150,1010; 1500,1200,1100,1550,1600,1550,1380,1070; 1500,1550,1600,1550,1600,1600,1600,1550; 1480,1500,1550,1510,1430,1300,1200,980;meshc(x0,y0,z0)xlabel(x);ylabel(y);zlabel(z)title(原始图) （1） 分段线性插值输入命令：xi2,yi2=meshgrid(1200:10:4000,1200:10:3600);zi2=interp2(x0,y0,z0,xi2,yi2,linear);meshc(xi2,yi2,zi2) xlabel(x);ylabel(y);zlabel(z)title(插值后) （2） 三次样条插值输入命令： xi,yi=meshgrid(1200:10:4000,1200:10:3600);zi=interp2(x0,y0,z0,xi,yi,spline);meshc(xi,yi,zi), title(三次样条插值表面图) xlabel(x);ylabel(y);zlabel(z) （3） 双三次插值输入命令：xi,yi=meshgrid(1200:10:4000,1200:10:3600);zi=interp2(x0,y0,z0,xi,yi,cubic);meshc(xi,yi,zi), title(双三次插值后的表面图)xlabel(x轴);ylabel(y轴);zlabel(z轴) （4）画等高线图：n=9;pcolor(x0,y0,z0)shading interpzmax=max(max(z0);zmin=min(min(z0);caxis(zmin,zmax)colorbarhold onC=contour(x0,y0,z0,n,k:);clabel(C)title(未拟合图形)hold off pcolor(xi,yi,zi)shading interpzmax1=max(max(zi);zmin1=min(min(zi);caxis(zmin1,zmax1)colorbarhold onC=contour(xi,yi,zi,n,k:);clabel(C)title(拟合图形)hold off 相应的图形中都画出了地貌图和等