How can I animate a parabolic function?

 %Here is my code to plot -x^2 slowly like the comet function:
x = linspace(0,4*pi,100);
for a = linspace(-10,10,200)
    y = -(x+a).^2;
    plot(x,y,'o')
    drawnow; 
    pause(1/40);
  end

So how can I edit it to look like the comet function smoothly?

Answer 1

[Star Strider]

Plotting it in real time will probably not result in the smoothness you want.

I would experiment with im2frame and movie.