编程不会写求指导，该怎么用matlab来写

Question

图上第二题，题目都有点看不懂，明明是一个球跟一个圆，如果r不输入具体数值matlab只会提醒未定义r，但啥也没说

Answer 1

你好可以这样做

r = 1;
theta = linspace(0, 2*pi, 1001);
phi = linspace(0, pi, 1001);
[T, P] = meshgrid(theta, phi);
x = r*cos(T).*sin(P);
y = r*sin(T).*sin(P);
z = r*cos(P);
p = x.^2+y.^2>r*x;
x(p) = nan;
y(p) = nan;
z(p) = nan;
mesh(x,y,z)
axis equal

效果