Interindividual distance from trajectories

At a given time frame, i have trajectories of 6 points having 6 X and 6 Y cordinates. I wish to calculate the distance between these points. Therefore, I will be obtaining 15 inter-point distances at a given frame. I wish to do so for n frames. Next, I would like to find the mean distance at a particular frame. How should I go about these? thank you in advance.

My data is in the form of text files (X and Y coordinates are in separate files- as attached).

Ishani

Edit: 15 inter-point distances, not 5 as pointed out by Chunru

[Chunru]

For 6 points having 6 X and 6 Y cordinates, you will have 5*6/2=15 paired distances.

doc pdist2

[Ishani Mukherjee]

Thank you for your pointing this out. Yes, at a given time I will have 15 distances.

Answer 1

[Chunru]

% xy = randn(6,2);
x = readmatrix("https://www.mathworks.com/matlabcentral/answers/uploaded_files/1153563/X_fragment1.txt");
y = readmatrix("https://www.mathworks.com/matlabcentral/answers/uploaded_files/1153573/Y_fragment1.txt");
whos

  Name          Size            Bytes  Class     Attributes

  cmdout        1x33               66  char                
  x           138x6              6624  double              
  y           138x6              6624  double              

nframes = size(x, 1);
dmean=zeros(nframes, 1);
for i=1:nframes
    xy = [x(i,:)', y(i, :)'];
    d = pdist2(xy, xy);
    % extract the lower triangle
    [ii, jj] = meshgrid(1:6, 1:6);
    d1 = d(ii>jj);  % d21, d31, ..., d61, d32, .., d62, ... d65
    dmean(i) = mean(d1);
end
plot(1:nframes, dmean)
xlabel('frame number');
ylabel('mean distance')

[Ishani Mukherjee]

Thank you for the answer. I am unable to run this. My data is in the form of X coordintes in .txt and Y in .txt coordinates separately. Further I have data fragmented in 3 parts. Is that why the codes are not running?

Example X cordinates:

907.78 674.62 1011.5 1266.2 638.22

907.53 674.53 1014.1 1268.8 638.22

907.81 674.06 1018.4 1271.4 639.56

907.11 673.45 1020.1 1273.8 639.56

907.9 671.81 1024.6 1277.2 638.42

907.85 672.24 1027.7 1274.2 638.42

907.61 671.76 1030.1 1267.1 638.42

907.37 671.32 1033.4 1260.4 6

[Chunru]

If you have difficulties reading the files, attach them in your post.

[Ishani Mukherjee]

Thank you for the response. I have done so.

[Chunru]

See the update for one group of data

[Ishani Mukherjee]

It's working, thank you so much,