Array to plot regarding position, please help

Hello there,

I am having a hard time with something.

I have an array of positions of 5 particles.

     -2.0000    5.0000    9.0000
      1.0000    2.0000    1.0000
      1.0000    2.0000    4.0000
      2.0000    4.0000    5.0000
      2.0000    4.0000    9.0000
      7.9593    7.3679   28.5506
      3.5556    2.6725   12.5232
     20.4053   11.7222   12.2861
      7.0142    9.7688   13.4013
      8.3092   12.7684   18.8180
     18.0262   10.7468   46.1048
      6.9414    4.9151   24.8694
     38.4836   21.5052   21.2306
     13.4649   18.3509   27.2144
     14.6882   21.1662   28.1150
     28.0050   14.4318   63.0786
     10.7245    7.9287   37.3743
     56.1209   31.2706   30.3044
     29.4162   48.6415   47.9855
     20.3663   27.7720   36.8458
     37.9202   18.2548   79.7830
     14.7593   11.4279   49.8749
     73.5533   41.0208   39.4236
     45.2485   78.5777   68.5677
     26.0782   34.3742   45.5945
     47.7897   22.1520   96.3300
     18.9727   15.2688   62.3179
     90.8710   50.7579   48.5628
     61.0552  108.4253   89.1036
     31.8039   40.9624   54.3531

Where each column represents X, Y, Z.

The array is somewhat confusing.

It is set up as follows: The first row is position of particle 1 at time=0 The second row is position of particle 2 at time=0 ... The fifth row is position of particle 5 at time=0 The sixth row is position of particle 1 at time=1 ... The last row is position of particle 5 at time = 5

Hope this makes sense.

Now I want to plot particles 1-5 from time=0-5

How can I do this?

Also is it possible to animate the progression of the particles? Thanks!

[Simon]

Hi!

So, what is the difference between this question and http://www.mathworks.com/matlabcentral/answers/106889-simulation-for-an-array?

Answer 1

[A Jenkins]

To make your matrix "less confusing" you can reshape it into a 3d matrix. For example:

myarray3=permute(reshape(myarray',3,5,[]),[3,1,2])

This would show the data grouped so you can easily see the position of the 5 particles at each time step.

myarray3(:,:,1) =

     -2.0000    5.0000    9.0000
      7.9593    7.3679   28.5506
     18.0262   10.7468   46.1048
     28.0050   14.4318   63.0786
     37.9202   18.2548   79.7830
     47.7897   22.1520   96.3300  

myarray3(:,:,2) =

      1.0000    2.0000    1.0000
      3.5556    2.6725   12.5232
      6.9414    4.9151   24.8694
     10.7245    7.9287   37.3743
     14.7593   11.4279   49.8749
     18.9727   15.2688   62.3179

etc...

Then you could use a for loop to go through each of the myarray(:,:,mytime) and plot the data. (Perhaps you want to use scatter3()...) Simon helped you out with how to do the animation in the post that he linked to.

[Nathan]

Ok I have reorganized my data. But when I try to plot it for the first particle using:

for j=1:time
    hold on
    plot3(pos(1,1,time),pos(1,2,time),pos(1,3,time),'-')
    F(j)=getframe;
end
movie(F)

The figure just resizes its axis and doesnt display anything really.

using the scatter3 just makes the data points flash all at once. There is no smooth animation from one frame to the next. Seems like all the data just gets dumped at once. I'm new to this so bare with me.

[A Jenkins]

1) To view the plot in 3d:

view(3)

2) To force the axis to stay the same size every time

axis([XMIN XMAX YMIN YMAX ZMIN ZMAX])

3) To plot all the particles instead of just the first one (and color code them):

scatter3(pos(:,1,time),pos(:,2,time),pos(:,3,time),[],jet(size(pos,1)),'filled')

4) To slow down the time between executing commands (if needed)

pause(1)