[lfssirius]

function plotcircle(n,center)
for i=1:n
subplotcircle(i,center);
hold on;
end
axis equal;
function subplotcircle(r,center)
t=linspace(-pi,pi,100);%%画100个点
x=cos(t)*r+center(1);
y=sin(t)*r+center(2);
plot(x,y)

画n个同心圆，以center为圆心