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Let's say: I have the matrix A containing of 5 points

A=[ 5 5 1 ----> coordinate (x,y,z) of point A1

4 5 2 ----> coordinate (x,y,z) of point A2

1 1 1 ----> coordinate (x,y,z) of point A3

2 3 1 ----> coordinate (x,y,z) of point A4

6 1 7 ] ----> coordinate (x,y,z) of point A5

And, I also have matrix B:

B=[ 0 2 1 ----> coordinate (x,y,z) of point B1

4 1 1 ] ----> coordinate (x,y,z) of point B2

How to find the Euclidean distance between each point in B and all points(1,2,3,4,5) in A.

Example:

distance between point B1 and points A1:

=sqrt{(5-0)^2+ (5-2)^2 + (1-1)^2}= 5.83

distance between point B1 and points A2

distance between point B1 and points A3

.......................................

distance between point B2 and points A1

distance between point B2 and points A2, A3,A4, A5

*I hope the result will be shown in matrix C(2-by-5)*

Rik
on 26 Oct 2017

Knowing my answer on your previous question, what do you think would be the solution? It isn't that hard. Of course you could solve this with a loop, but there is a direct solution, for which you can use functions like repmat.

Show some effort.

Andrei Bobrov
on 26 Oct 2017

Edited: Andrei Bobrov
on 26 Oct 2017

Or

Dista = squeeze(sqrt(sum((A - reshape(B',1,3,[])).^2,2))); % New MATLAB

Dista = squeeze(sqrt(sum(bsxfun(@minus,A,reshape(B',1,3,[])).^2,2))); % Old MATLAB

KSSV
on 26 Oct 2017

doc pdist and pdist2.

Rik
on 27 Oct 2017

Typing doc pdist will open the documentation for the pdist function, which you can also find online. If you look at the 'see also' section, you will a find reference to the pdist2 function.

Knowing how to look for and read the documentation is a very useful skill. Extremely easy to learn, sometimes hard to master. Using your favorite internet search engine also helps out a lot.

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