How to find distance between different points in a dataset as shown in scatter plot

Hi,

This is my scatter plot data of 5 simulated points and data in blue is my reference point and I want to compute the distance of this blue data from other data set one by one. As all data sets are of equal dimension [1x51] and when I am computing the distance then it is giving me error of Sub-scripted assignment dimension mismatch.

I have attached the ns.mat file and I want distance matrix with distance of (1 from 2),(1 from 3),(1 from 4),(1 from 5). Need your guidance.

if true
for time = 0:0.2:10
 for i=1:numData
 for j=1:len_data
 % Get first sensor x and y coordinates
  tx = [ns(1).x];
  ty = [ns(1).y];
 % Compute distances
  distance_nhood(i,j) = sqrt((tx- ns(i).x(j)).^2 + (ty- ns(i).y(j)).^2);
  % If distance is less than 5, draw a line to it.
  % First find which nodes are closest.
  neighbourNodes = find(distance_nhood < 5);
      .............
  %%coding continue
      .............
 end
end
        connMatrix = ( distance_nhood< txRange); 
      % Get the number of reachable neighbors
       neighborNodes = find(neighbourNodes (1, :) == 1);   % logic to think 
      % Get the unreached neighbors
       neigbborNodes = intersect(neighborNodes, find(visited(:) == 0));% logic to think
end

[Walter Roberson]

Which line is it producing the error on?

[Arsal15]

This line is producing error.

if true
  distance_nhood(i,j) = sqrt((tx- ns(i).x(j)).^2 + (ty- ns(i).y(j)).^2);
end

I want to compute distance of first node with rest of other nodes, i.e.for each data points of node1 to other nodes.

[Arsal15]

any better and efficient way to do this.

if true
  XY = zeros(len_x,2);
  xrest = zeros(numData-1,len_x);
  yrest = zeros(numData-1,len_x);
  dist_mat =zeros(len_x,numData-1);
  XY = [ns(1).x',ns(1).y'];
  for k = 2:numData
      xrest(k,:) = ns(k).x; 
      yrest(k,:) = ns(k).y; 
      xrest = xrest';
      yrest = yrest';
      dist_mat(:,k) = sqrt((xrest(:,k)-XY(:,1)).^2+(yrest(:,k)-XY(:,2)).^2);
  end
 end

[Brendan Hamm]

You are trying to assign to a scalar element of distance_nhood an entire vector and this is a dimension mismatch. The reason for this is that tx and ty are both vectors and not the first node.