Getting Started |

**Creating Movies**

If you increase the number of points in the Brownian motion example to something like `n = 300`

and `s = .02`

, the motion is no longer very fluid; it takes too much time to draw each time step. It becomes more effective to save a predetermined number of frames as bitmaps and to play them back as a *movie*.

First, decide on the number of frames, say

Next, set up the first plot as before, except using the default `EraseMode`

(`normal`

).

x = rand(n,1)-0.5; y = rand(n,1)-0.5; h = plot(x,y,'.'); set(h,'MarkerSize',18); axis([-1 1 -1 1]) axis square grid off

Generate the movie and use `getframe`

to capture each frame.

for k = 1:nframes x = x + s*randn(n,1); y = y + s*randn(n,1); set(h,'XData',x,'YData',y) M(k) = getframe; end

Finally, play the movie 30 times.

Animations | Programming with MATLAB |