compute_nn_distance.m

toolbox_dimreduc - a toolbox for dimension reduction methods This toolbox is an educational and rec

function [D,nn_list] = compute_nn_distance(X,nbr_nn, options)

% compute_nn_distance - compute the distance to the nearest neighbors
%
%   [D,nn_list] = compute_nn_distance(X,nbr_nn, options);
%
% X is a (d,n) set of n points in R^d
% nbr_nn is the number of nearest neighbors to retrieve
%
% D is a (n,nbr_nn) matrix of distance, D(i,j) is distance between point
%   X(:,i) and point X(nn_list(i,j),:)
% nn_list(i,:) is the set of nearst neighbors
%
%   options.use_nntools = 0 force the use of the slow matlab code
%       for nearest neighbors computations.
%
%   options.exlude_self = 1 to avoid taking a point it self neighbor.
%
%   Copyright (c) 2006 Gabriel Peyr