I need to plot a trajectory, of a point on circumference of a circle moving around its centre and centre is moving along its x-axis.

% please help i dont undrestand

Answer 1

[KSSV]

% cicle 
th = linspace(0,2*pi) ; 
r = 1. ; 
xc = r*cos(th) ; 
yc = r*sin(th) ; 
% center of circle movine along ax axes 
x = linspace(0,15,100) ; 
y = zeros(size(x)) ; 
% plot 
for i = 1:length(x)
  figure(1)
  for j = 1:length(xc)
    plot(x(i)+xc(1:j),y(i)+yc(1:j)) ; 
    axis([-5 15 -2 2])
    drawnow
  end

end

Better is to use set. Read about it.