How to use a function for multiple sets of numbers with a single command?

For instance, I created a function to calculate the distance between 2 points with X,Y coordinates with this formula:

D=sqrt((X1-X2)^2+(Y1-Y2)^2)

                               Point nb.   X    Y
and I have this matrix: A =        1     2800 3500
                                   2     4200 5300
                                   3     5100 6200
                                   -      -    -
                                   -      -    -
                                   n      x    y
The dimension of matrix A is ,,n" rows and 2 columns

Now, how I can apply this function to calculate distances between points 1&2, 2&3, 3&4 and so on, with a single command?Is it possible?

*Note: English is not my first language, and I may have not been very explicit

Answer 1

[Andrei Bobrov]

k = diff(A);
D = hypot(k(:,1),k(:,2)); % I am corrected after Sean's comment.

On Ciuban's comment.

Try used function pdist from Statistics Toolbox:

A =    [2800        3500
        4200        5300
        5100        6200];
D = pdist(A);

[Sean de Wolski]

Why the num2cell()?

[Sebastian Ciuban]

Its working. You are very helpful guys, thank you very much. 1 more thing I want to discuss. Now, its possible to make this function calculate every combination of points? At the moment it calculates distances between 1&2, 2&3, 3&4 and so on. What I need to do to make that command calculate 1&4, 2&4 and every combination possible? Once again, thank you very much for your help

[Mahdi]

Look at my answer and where ever you see A(2:end) and A(1:end) changes how far you want to go.

For example, if you want 1&4 and 2&4, you would use A(4:end) and A(2:end-4) respectively. Try to explore the colon operator and see what it does. For example, try the following

A=[1 2 3; 4 5 6; 7 8 9];
A(1:2:end, 1)
A(1:3:end)
A(1, 1:2:end)
A(1:3,1)

[Matt Kindig]

Ciuban, if you want every combination, it sounds like you want to calculate the inter-point distance matrix. This can get very memory-intensive if done poorly/naively, so I'd recommend using one of the File Exchange solutions for this. I'd recommend:

href = ""<http://www.mathworks.com/matlabcentral/fileexchange/18937-ipdm-inter-point-distance-matrix</a>>

Answer 2

[Mahdi]

D=sqrt((A(2:end,2)-A(1:end-1,2)).^2+(A(2:end,3)-A(1:end-1,3)).^2)

[Sebastian Ciuban]

Thank you for your answer but after I put that command MatLab it shows me this error ,,Index exceeds matrix dimensions".

[Mahdi]

Is your matrix A as you've shown it? Or is it only 2 columns?

[Matt Kindig]

What are the dimensions of A? Based on your example, it is a bit unclear.

[Sebastian Ciuban]

the dimension of A is ,,n" rows and 2 columns

[Matt Kindig]

Then you can just modify Mahdi's code as:

D=sqrt((A(2:end,2)-A(1:end-1,2)).^2+(A(2:end,1)-A(1:end-1,1)).^2)