Creating a row of points

Hi guys, I am trying to make an animated plot, where I want to plot a trail/row of points as it follows:

 xe1 = (-lm/2)+Vest*t;
 for j=1:1:length(t)
 if xe1(j)>(2*lm)
   xe1(j)=(-lm/2);
 end
 end

For instance, xe1 indices should change so that xe2 = (-lm/2)+(lm/4)+Vest*t, i.e., xe(i+1) = xe(i)+lm/4.

How can I add this condition to this already existing loop? Thank you!

Answer 1

[Walter Roberson]

N = 5;
Nt = length(t);
xe = zeros(N, Nt);
xe(1,:) = (-lm/2)+Vest*t;
for K = 1 : N
  idx = xe(K,:) > 2*lm;
  xe(K,idx) = -lm/2;
  if K ~= N
    xe(K+1,:) = xe(K,:) + lm/4;
  end
end

plot(xe.');  %if you want N lines