ComputeDiversity

 [Val] = ComputeDiversity(Pop) 
 ComputeDiversity: Computes the average quadratic distance between each pair of vectors
                   in  Pop.
 INPUTS
 Pop: Each row corresponds to a vector
 Val: Average square difference between pairs of vectors

 Last version 2/26/2009. Roberto Santana (roberto.santana@ehu.es)

0001 function[Val] = ComputeDiversity(Pop) 
0002 % [Val] = ComputeDiversity(Pop)
0003 % ComputeDiversity: Computes the average quadratic distance between each pair of vectors
0004 %                   in  Pop.
0005 % INPUTS
0006 % Pop: Each row corresponds to a vector
0007 % Val: Average square difference between pairs of vectors
0008 %
0009 % Last version 2/26/2009. Roberto Santana (roberto.santana@ehu.es)
0010 
0011  Val = 0;
0012  
0013  [PopSize,n] = size(Pop);
0014  npairs = PopSize*(PopSize-1)/2;
0015  for i=1:PopSize-1,
0016   for j=i+1:PopSize,
0017     Val = Val + sum((Pop(i,:)-Pop(j,:)).^2); 
0018   end
0019  end
0020  
0021  Val = Val/(npairs);