Create timeseries of a 3d scattered plot

Hello all,

I have a dataset displayed in a 3D scattered plot superimposed with a closed cylinder.

I wish to plot a time series (movie) showing when each scattered plot point was recorded in the scattered plot.

Below is my interial code:

A = 25*rand(8, 5)

A = 8×5

13.0818 5.5140 14.0092 14.8775 8.8787 23.6924 1.5850 15.8762 6.1108 21.2250 19.1817 16.4236 10.1666 17.3767 18.8237 0.4604 13.5761 3.5632 13.5605 2.1653 21.7514 1.2951 20.0804 19.2080 18.5357 5.8638 0.6297 13.3577 8.0470 14.8173 13.1569 8.0734 15.7814 14.1187 24.2023 4.2932 3.9761 21.4168 24.2942 15.3522

Time = A (:,1) ;
x = A (:,2 ) ;
y = A (:,3 ) ;
z = A (:,4 ) ;
Amplitude = A (:,5) ; 
scatter3 (x , y, z, 30, Amplitude); 
title ('Sample Material')
xlim ([-50.00 50.00])
ylim ([-50.00 50.00])
zlim ([0.00 100.00])
xlabel ('Breath /m')
ylabel ('Width /m')
zlabel ('Height /m')
pbaspect([1 1 2])
H = colorbar ;
ylabel (H, 'Amplitude') 
hold on
r = 25.000;
[X,Y,Z] = cylinder(r);
hsurf = surf (X,Y,Z*100, 'EdgeColor', 'none', 'FaceAlpha', 0.2); % capture the handle of the surf object
patch(X(1,:),Y(1,:),Z(1,:), hsurf.CData(1,:), 'FaceAlpha', 0.2)
patch(X(1,:),Y(1,:),Z(2,:), hsurf.CData(1,:), 'FaceAlpha', 0.2)

My current challenge comes from adding the time series. I will be grateful to have some comments on how to proceed.

Here is my additional code for the timespan:

ts1 = timeseries(A (:,1), x,y,z,Amplitude); 
ts1.Name = 'Sample Material - Time Span';
ts1.TimeInfo.Units = 'hours';
ts1.TimeInfo.StartTime = '00.00';
ts1.TimeInfo.Format = 'hh mm, ss'; 
ts1.Time = ts1.Time - ts1.Time(1);
plot(ts1);

Thank you.

[Simon Chan]

Simply using a for loop and a pause may create a movie-like presentation.

Try the following to see whether this is what you want.

for k = 1:10
    A = 25*rand(8, 5);
    Time = A (:,1) ;
    x = A (:,2 ) ;
    y = A (:,3 ) ;
    z = A (:,4 ) ;
    Amplitude = A (:,5) ; 
    scatter3 (x , y, z, 30, Amplitude);
    ax = gca;
    title ('Sample Material')
    xlim ([-50.00 50.00])
    ylim ([-50.00 50.00])
    zlim ([0.00 100.00])
    xlabel ('Breath /m')
    ylabel ('Width /m')
    zlabel ('Height /m')
    pbaspect([1 1 2])
    H = colorbar ;
    ylabel (H, 'Amplitude') 
    hold(ax,'on')
    r = 25.000;
    [X,Y,Z] = cylinder(r);
    hsurf = surf (X,Y,Z*100, 'EdgeColor', 'none', 'FaceAlpha', 0.2); % capture the handle of the surf object
    patch(X(1,:),Y(1,:),Z(1,:), hsurf.CData(1,:), 'FaceAlpha', 0.2);
    patch(X(1,:),Y(1,:),Z(2,:), hsurf.CData(1,:), 'FaceAlpha', 0.2);
    pause(1);
    hold(ax,'off');
end

[Greek McCoy]

Hello,

Thank you for your response.

The loop and pause option is helpful but the challenge I have with that is all scattered points are displayed on the graph at the same time. My intention is to display each scattered point on the graph with respect to the time

Time = A (:,1) %in hours

until all points are captured on the same graph.

Will it be possible to execute such an idea?

Thank you.

[Simon Chan]

Modify slightly and let see the following is what you want? You may use this as the starting point.

for k = 1:10
    A = 25*rand(8, 5);
    Time = A (:,1) ;
    x = A (:,2 ) ;
    y = A (:,3 ) ;
    z = A (:,4 ) ;
    Amplitude = A (:,5) ;
    scatter3 (x , y, z, 30, Amplitude);
    ax = gca;
    if k == 1
        title ('Sample Material')
        xlim ([-50.00 50.00])
        ylim ([-50.00 50.00])
        zlim ([0.00 100.00])
        xlabel ('Breath /m')
        ylabel ('Width /m')
        zlabel ('Height /m')
        pbaspect([1 1 2])
        H = colorbar ;
        ylabel (H, 'Amplitude') 
        hold(ax,'on')
        r = 25.000;
        [X,Y,Z] = cylinder(r);
        hsurf = surf (X,Y,Z*100, 'EdgeColor', 'none', 'FaceAlpha', 0.2); % capture the handle of the surf object
        patch(X(1,:),Y(1,:),Z(1,:), hsurf.CData(1,:), 'FaceAlpha', 0.2);
        patch(X(1,:),Y(1,:),Z(2,:), hsurf.CData(1,:), 'FaceAlpha', 0.2);
    else
    pause(1);
    end
end

[Greek McCoy]

Hello,

Thank you for your reply. I tried this option.

Could you kindly tell me what you mean by I may use this as the starting point?

The code works well for my first line of dataset then subsequently not.

The idea is to present the evolution of the scattered data on the same graph with respect to time.

Time = A (:,1) ; %Time in hours from the dataset 

Perhaps, I should draft the question better and submit again?

Thank you

Answer 1

[Ive J]

If you want to create an animation (GIF for instance) or a movie (e.g. AVI), you can:

% see: https://mathworks.com/matlabcentral/answers/94495-how-can-i-create-animated-gif-images-in-matlab
for i = 1:20
    A = 25*rand(8, 5);
    Time = A (:,1) ;
    x = A (:,2 ) ;
    y = A (:,3 ) ;
    z = A (:,4 ) ;
    Amplitude = A (:,5) ; 
    scatter3 (x , y, z, 30, Amplitude); 
    title ('Sample Material')
    xlim ([-50.00 50.00])
    ylim ([-50.00 50.00])
    zlim ([0.00 100.00])
    xlabel ('Breath /m')
    ylabel ('Width /m')
    zlabel ('Height /m')
    pbaspect([1 1 2])
    H = colorbar ;
    ylabel (H, 'Amplitude') 
    hold on
    r = 25.000;
    [X,Y,Z] = cylinder(r);
    hsurf = surf (X,Y,Z*100, 'EdgeColor', 'none', 'FaceAlpha', 0.2); % capture the handle of the surf object
    patch(X(1,:),Y(1,:),Z(1,:), hsurf.CData(1,:), 'FaceAlpha', 0.2)
    patch(X(1,:),Y(1,:),Z(2,:), hsurf.CData(1,:), 'FaceAlpha', 0.2)
    hold off
    drawnow

    frame = getframe(gcf);
    im = frame2im(frame); 
    [imind,cm] = rgb2ind(im,256); 
    if i == 1 
      imwrite(imind, cm, 'myanimation.gif', 'gif', 'Loopcount', 1); 
    else 
      imwrite(imind, cm, 'myanimation.gif', 'gif', 'WriteMode', 'append'); 
    end 
end

Similarly, for a movie:

for i = 1:20
 % plot
 drawnow
 
 f(i) = getframe(gcf);
end

vidobj = VideoWriter('mymovie.avi');
vidobj.FrameRate = 10;
open(vidobj);
for i = 1:numel(f); writeVideo(vidobj, f(i)); end
close(vidobj);

[Greek McCoy]

Hello,

Thank you very much for your response and the attached reference. They have been very helpful.

I have tried your examples which work well. I however have a challenge when I try to replace

A = 25*rand(8, 5); 

in the code with loading a .txt file

A = load ('sampleMaterial.txt');

Is there a way that I could load a .txt file and display each scattered plot point with respect to time

Time = A (:,1) ; %Time in hours from the dataset 

in a gif or video as your examples?

Thank you once again.

[Ive J]

can you attach 'sampleMaterial.txt'?

[Greek McCoy]

Yes, please find it atatched.

Thank you

[Ive J]

Assuming you deleted the first line in the text file:

A = readtable('sampleMaterial.txt');
for i = 1:A.Time
    scatter3 (A.x(i) , A.y(i), A.z(i), 30, A.Amplitude(i), 'filled'); 
    title ('Sample Material')
    xlim ([-50.00 50.00])
    ylim ([-50.00 50.00])
    zlim ([0.00 100.00])
    xlabel ('Breath /m')
    ylabel ('Width /m')
    zlabel ('Height /m')
    title(compose("Time = %.2f s", A.Time(i)))
    pbaspect([1 1 2])
    H = colorbar ;
    ylabel (H, 'Amplitude') 
    hold on
    r = 25.000;
    [X,Y,Z] = cylinder(r);
    hsurf = surf (X,Y,Z*100, 'EdgeColor', 'none', 'FaceAlpha', 0.2); % capture the handle of the surf object
    patch(X(1,:),Y(1,:),Z(1,:), hsurf.CData(1,:), 'FaceAlpha', 0.2)
    patch(X(1,:),Y(1,:),Z(2,:), hsurf.CData(1,:), 'FaceAlpha', 0.2)
    hold off
    drawnow
    frame = getframe(gcf);
    im = frame2im(frame); 
    [imind,cm] = rgb2ind(im,256); 
    if i == 1 
      imwrite(imind, cm, 'myanimation.gif', 'gif', 'Loopcount', 1); 
    else 
      imwrite(imind, cm, 'myanimation.gif', 'gif', 'WriteMode', 'append'); 
    end 
end

[Greek McCoy]

Thank you very much for your response. The code works well now.

I am trying to adjust it now to show a cummulation of the points as the time elapsed.

Thank you once again.

--

Greek

[Ive J]

Just remove hold off...

[Greek McCoy]

Hello,

I eventually figured that out. You've been so helpful.

I am now going to practice with several lines of the same data.

Thank you once more.

[Ive J]

My pleasure