Distance from points to points.

It's possible to read these coordinates from a text file formatted in this way:

[Image Analyst]

Isn't this a duplicate of http://www.mathworks.com/matlabcentral/answers/114838#answer_123302 which already has people responding?

[Francesco]

It's not exactly the same questions.

Answer 1

[Walter Roberson]

http://www.mathworks.com/help/stats/pdist.html

The identifier would be the row index of D.

[Francesco]

[X, Y] = ndgrid(1:N);
   identifiers = arrayfun(@(X,Y) sprintf('%d_%d', X, Y), X, Y, 'Uniform', 0);

When you before said this, what do you mean with N? What's the index of D?

[Walter Roberson]

You had N points.

D refers to the output of pdist.

[Francesco]

Thanks. In general If I have n points I have to do this, where rows is the numbers of rows of the txt file.

[X, Y] = ndgrid(1:rows);
identifiers = arrayfun(@(X,Y) sprintf('%d_%d', X, Y), X, Y, 'Uniform', 0);

How Can I use pdist? What can I enter as input?

[Walter Roberson]

Your previous question asked about using identifiers of that form and defined what the identifiers should look like. This question asks about using linear identifiers of the form 1, 2, 3, ... 6 .... n*(n-1)/2. But you have not given any indication of how the two are to fit together.