[mathjiang]

可以运行了（删除了几个多余的语句）：
q=0; r=0.2; e=0.4; t=0;
w1=2; w2=1; s=0;
x=zeros(1,5000);
x(1)=r*cos(q)+e;
y=zeros(1,5000);
for i=1:5000-1
t=t+pi/500;
x(i+1)=r*cos(q+w2*t-w1*t)+e*cos(w1*t);
y(i+1)=r*sin(q+w2*t-w1*t)+e*sin(w1*t);
if (x(i)^2+y(i)^2)^0.5>0.3
s=s+((x(i+1)-x(i))^2+(y(i+1)-y(i))^2)^0.5;
end
end
s