https://github.com/PerezOrtegaJ/Neural_Ensemble_Analysis
Tip revision: 9d37fd031dfbdb4eb69faa449d0a6416267a7d4f authored by Jesús Pérez on 28 July 2020, 20:36:58 UTC
Update README.md
Update README.md
Tip revision: 9d37fd0
DunnIdx_JP.m
% Dunn's Index
% Get the Dunn's index for g groups given a distance matrix.
%
% [DI] = DunnIdx(g,dist,idx)
%
% Inputs
% g = number of groups
% dist = square distance matrix
% idx = indexes of group to which each data point belongs
%
% Outputs
% DI = Dunn's index
%
% ..:: by Jesús E. Pérez-Ortega ::.. Mar-2012
function [DI] = DunnIdx_JP(g,dist,idx)
min_inter=[]; % minimal distance inter-group
max_intra=[]; % maximal distance intra-group
for i=1:g
g_i=find(idx==i);
g_other=find(idx~=i);
min_inter(i)=min(min(dist(g_i,g_other)));
max_intra(i)=max(max(dist(g_i,g_i)));
end
min_inter=min(min_inter);
max_intra=max(max_intra);
DI=min_inter/max_intra;