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Topic: Euclidean distance of all pairwise combinations (redundants)
Replies: 7   Last Post: Nov 18, 2012 4:02 AM

 Messages: [ Previous | Next ]
 Ralph Dratman Posts: 62 Registered: 5/13/11
Re: Euclidean distance of all pairwise combinations (redundants)
Posted: Nov 15, 2012 4:02 AM

Jesse,

Just use Tuples instead of Subsets. Nothing else changes.

EuclideanDistance @@@ Tuples[list, {2}]

{0, Sqrt[2], 2 Sqrt[2], Sqrt[2], 0, Sqrt[2], 2 Sqrt[2], Sqrt[2], 0}

Is that what you are looking for?

Ralph Dratman

On Wed, Nov 14, 2012 at 1:29 AM, Jesse Pisel <jessepisel@gmail.com> wrote:

> I have been having a tough time trying to figure out how to include all
> red undant pairwise combinations in my results for the euclidean distance
> between a set of points. I have a set of points with xy coordinates and
> want the euclidean distance between each point including the point and
> itself. So if my points in xy space are list = {{1, 1}, {2, 2}, {3, 3}} for
> example, I want the distance from {1, 1} to {1, 1}, {1, 1} to {2, 2}, and
> {2, 2} to {3, 3} etc. for each point for a total of 9 distances all
> together. The EuclideanDistance function removes the redundant distances
> that I want retained in the results. I have been using this code just to
> play with data but would like to be able to expand up to 500+ points:
>
> list = {{1, 1}, {2, 2}, {3, 3}}
> EuclideanDistance @@@ Subsets[list, {2}]
>
> Any ideas on how to get the euclidean distance between all the points
> including redundants and self references?
>
>
>

Date Subject Author
11/15/12 Ralph Dratman
11/15/12 Sseziwa Mukasa
11/15/12 Jesse Pisel
11/15/12 Bob Hanlon
11/15/12 Bob Hanlon
11/17/12 Dana DeLouis
11/18/12 Joseph Gwinn