Re: [R] From Distance Matrix to 2D coordinates

On Thu, Dec 15, 2011 at 10:47 AM, Lorenzo Isella wrote: > Thanks a lot! > Precisely what I had in mind. > One last question (an extension of the previous one): can this be extended > to points in 3D? Once again, given the distance matrix, can I reconstruct a > set of coordinates (among many possib

Re: [R] From Distance Matrix to 2D coordinates

Thanks a lot! Precisely what I had in mind. One last question (an extension of the previous one): can this be extended to points in 3D? Once again, given the distance matrix, can I reconstruct a set of coordinates (among many possible) for the points in three-dimensional space? Cheers Lorenzo

[R] From Distance Matrix to 2D coordinates

On Thu, Dec 15, 2011 at 10:08 AM, Lorenzo Isella wrote: > Dear All, > I am struggling with the following problem: I am given a NxN symmetric > matrix P ( P[i,i]=0, i=1...N and P[i,j]>0 for i!=j) which stands for the > relative distances of N points. > I would like use it to get the coordinates of

Re: [R] From Distance Matrix to 2D coordinates

That's exactly what ordination is for (not clustering). I'd try principal coordinates analysis, or non-metric multidimensional scaling, depending on whether the dissimilarity you'v been given is metric or nonmetric. There are implementations of both in the ecodist package, and in various other pa

[R] From Distance Matrix to 2D coordinates

Dear All, I am struggling with the following problem: I am given a NxN symmetric matrix P ( P[i,i]=0, i=1...N and P[i,j]>0 for i!=j) which stands for the relative distances of N points. I would like use it to get the coordinates of the N points in a 2D plane. Of course, the solution is not uniq