How to make a video from comet(x, y) command?

I am trying to record a movie using the comet(x, y) command. To record a movie I use the following commands:

drawnow
movieVector(k) = getframe(gcf);

these are inside a lopp and:

v = VideoWriter('L3 Orbits', 'MPEG-4');
v.FrameRate = 100;
open(v);
writeVideo(v, movieVector)
close(v);

which are outside of the loop.

The issue is I need to capture more frames than just one frame per trajectory. I don't know how to do this.

Answer 1

[Walter Roberson]

You cannot do this while using comet() . comet() does not return until all of the drawing is complete .

These days comet() is implemented in terms of animatedLine() and addpoints() and drawnow() . That is probably the same strategy you should use to create the movie.

Answer 2

[Balaji]

Hi Mark,

To capture more frames per trajectory when recording a movie using the `comet` command in MATLAB, you can modify your code as follows:

v = VideoWriter('L3 Orbits', 'MPEG-4');
v.FrameRate = 100;
open(v);
for k = 1:numTrajectories
    comet(x, y);
    numFramesPerTrajectory = 100;
    movieVector = struct('cdata', cell(1, numFramesPerTrajectory), 'colormap', cell(1, numFramesPerTrajectory));
    for frame = 1:numFramesPerTrajectory
        drawnow;
        movieVector(frame) = getframe(gcf);
    end
    writeVideo(v, movieVector);
end

close(v);

Thanks,

Balaji

[Mark]

I still do not get a video output.

I've attached the main script 'Comet_Plot.m' and the supporting function files: 'pcr3bp.m', 'trajGet3BP.m', and 'Rotation_Rot2Iner.m'.

[Balaji]

Please insert the following line of code after the `movie_vector` has finished updating, at line 109 in `Comet_Plot.m`:

writeVideo(v, movieVector);