maanmian.m

最近一段数学建模源程序汇编,适用于建模初学者练习

clf,a=-20;eps0=1;
[x,y]=meshgrid(-10:0.2:10);
v=[-10 10 -10 10 -100 100];
colormap(gray)
z1=(x.^2-2*y.^2)+eps;
z2=a*ones(size(x));
r0=abs(z1-z2)<=eps0;
zz=r0.*z2;
xx=r0.*x;
yy=r0.*y;
subplot(2,2,2),
h1=plot3(xx(r0~=0),yy(r0~=0),zz(r0~=0),'+');
set(h1,'markersize',2),hold on,axis(v),grid on
subplot(2,2,1),
mesh(x,y,z1);grid,hold on;mesh(x,y,z2);
h2=plot3(xx(r0~=0),yy(r0~=0),zz(r0~=0),'.');
set(h2,'markersize',6),hold on,axis(v),
for i=1:5
    a=70-i*30;
    z2=a*ones(size(x));r0=abs(z1-z2)<=1;zz=r0.*z2;yy=r0.*y;xx=r0.*x;
    subplot(2,2,3),
    mesh(x,y,z1);grid,hold on;mesh(x,y,z2);hidden off
    h2=plot3(xx(r0~=0),yy(r0~=0),zz(r0~=0),'.');axis(v),grid
    subplot(2,2,4),
    h4=plot3(xx(r0~=0),yy(r0~=0),zz(r0~=0),'o');
    set(h4,'markersize',2),hold on,axis(v),grid on
end