Incremental display of data points in a 3D scattered plot

Dear all,

I have with me the attached dataset which I will like to display by a gradual representation (accumulation of the plot points in a point by point format until all plot points are displayed) in a scattered plot.

Below here is my code:

%clear all;
%close all;
clc

A = load ('TimespanTutorial.txt');
Time = A (:,1) ;
x = A (:,2 ) ;
y = A (:,3 ) ;
z = A (:,4 ) ;
Amplitude = A (:,5) ; 
scatter3 (x , y, z, 30, Amplitude); 
    title ('TimespanTutorial')
    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); 
    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 
for i = 1:A (:,1)
    frame = getframe(gcf);
    im = frame2im(frame); 
    [imind,cm] = rgb2ind(im,256); 
    if i == 1 
      imwrite(imind, cm, 'myanimation.gif', 'gif', 'Loopcount', 100); 
    else 
      imwrite(imind, cm, 'myanimation.gif', 'gif', 'WriteMode', 'append'); 
    end
end 

My results show all the plot points in the graph accurately but not in an incremental sequence as desired.

Is there any possibilty that I may get some assitance?

I am open to saving the incremental display of the plot points as photos to create a short movie afterwards.

Answer 1

[Mathieu NOE]

hello

this would be my suggestion

adapt the amount of pause to your needs

all the best

clc
A = load ('TimespanTutorial.txt');
Time = A (:,1) ;
x = A (:,2 ) ;
y = A (:,3 ) ;
z = A (:,4 ) ;
Amplitude = A (:,5) ; 
scatter3 (x(1) , y(1), z(1), 30, Amplitude(1)); 
    title ('TimespanTutorial')
    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); 
    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)

%     gif first frame export
    frame = getframe(gcf);
    im = frame2im(frame); 
    [imind,cm] = rgb2ind(im,256); 
      imwrite(imind, cm, 'myanimation.gif', 'gif', 'Loopcount', numel(Amplitude));    
      
for ci = 2:numel(Amplitude)
    
    scatter3 (x(ci) , y(ci), z(ci), 30, Amplitude(ci)); 
    pause(0.25);
    drawnow
%    gif remaining frames export
    frame = getframe(gcf);
    im = frame2im(frame); 
    [imind,cm] = rgb2ind(im,256); 
    imwrite(imind, cm, 'myanimation.gif', 'gif', 'WriteMode', 'append'); 
    
end 

    hold off

[Greek McCoy]

Hello Mathieu,

Thank you very much for your assistance. The code is working as expected.

The only challenge has been that the Amplitude legend shows a particular range (36 - 38) upon running the code. When a change of the standard colormaps is effected, the legend reverts to betweeen 0 - 100 as it should.

Is this something that I can fix in the code straightaway?

Thank you once again.

--

Sincerely,

GM

[Mathieu NOE]

hello Greek

on my side I see no changes in the Amplitude legend (you mean the colorbar min / max values) ?

the plot is exactly as in your original code exept that the scatter points are added one by one

no other visual difference here on my side

attached the animated gif I generated

[Mathieu NOE]

just for safety

with caxis I force the colorbar min / max values from the start.

for my own pleasure I changed also the colormap to jet for more colored contrast !

animated gif in attachment

clc
A = load ('TimespanTutorial.txt');
Time = A (:,1) ;
x = A (:,2 ) ;
y = A (:,3 ) ;
z = A (:,4 ) ;
Amplitude = A (:,5) ; 
scatter3 (x(1) , y(1), z(1), 30, Amplitude(1)); 
    title ('TimespanTutorial')
    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 ;
colormap('jet');
caxis([min(Amplitude) max(Amplitude)]);

    ylabel (H, 'Amplitude') 
    hold on
    r = 25.000;
    [X,Y,Z] = cylinder(r);
    hsurf = surf (X,Y,Z*100, 'EdgeColor', 'none', 'FaceAlpha', 0.2); 
    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)

%     gif first frame export
    frame = getframe(gcf);
    im = frame2im(frame); 
    [imind,cm] = rgb2ind(im,256); 
      imwrite(imind, cm, 'myanimation.gif', 'gif', 'Loopcount', numel(Amplitude));    
      
for ci = 2:numel(Amplitude)
    
    scatter3 (x(ci) , y(ci), z(ci), 30, Amplitude(ci)); 
    pause(0.25);
    drawnow
%    gif remaining frames export
    frame = getframe(gcf);
    im = frame2im(frame); 
    [imind,cm] = rgb2ind(im,256); 
    imwrite(imind, cm, 'myanimation.gif', 'gif', 'WriteMode', 'append'); 
    
end 

    hold off

[Greek McCoy]

Hello Mathieu,

I appreciate your prompt response and the attached files.

The idea of a forced min / max value colorbar is more suitable and works to perfection.

Thank you so much for your assistance.

--

Regards,

GM

[Mathieu NOE]

My pleasure !

all the best