Date: Nov 15, 2012 4:02 AM
Author: Ralph Dratman
Subject: Re: Euclidean distance of all pairwise combinations (redundants)


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?
>
>
>