How to animate a cosine plot using getframe

Hi, I'm pretty new to Matlab and I've been playing around trying to animate a 2D cosine graph using the getframe function. Here's my code

t=0:pi/100:10;
tlength = numel(t);
for i=1:tlength
    plot(cos(t));
    F(:,i) = getframe; 
end
movie(F);

But when I try running it it's not animated at all, just a still plot. What am I doing wrong?

Answer 1

[KSSV]

t=0:pi/100:10;
tlength = numel(t);
for i=1:tlength
    plot(cos(1:t(i)));
    F(:,i) = getframe; 
end
movie(F);

Also read about comet

t=0:pi/100:10;
y = cos(t) ;
comet(t,y)

[jm]

Thank you so so so much!

[KSSV]

Thanks is accepting the answer... :)