function [BTRAIN,CNTER]=replica(TNSPEC,B)
%  TNSPEC=training spectra, B=number of replicates desired. 
%  REPLICA outputs BTRAIN replicates, and the center of the replicates in CNTER
%
% "Copyright 2003 Robert A. Lodder & Bin Dai"
%
% This program is free software; you can redistribute it and/or
% modify it under the terms of the GNU General Public License
% as published by the Free Software Foundation; either version 2
% of the License, or (at your option) any later version.
% 
% This program is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
% GNU General Public License for more details.
% 
% You should have received a copy of the GNU General Public License
% along with this program; if not, write to the Free Software
% Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
% 
% Contact Information located at www.pharm.uky.edu or search the World Wide Web
% for Analytical Spectroscopy Research Group.
 
  [N,D]=size(TNSPEC);
  BTRAIN=zeros(B,D);
  CNTER=zeros(D,1);
  BSAMP=zeros(N,D);
  PICKS=rand(B*N,1);
  index=find(PICKS==1);
  PICKS(index)=0.9999;  
  PICKS=reshape(PICKS,B,N);
  PICKS=fix(N*PICKS+1);
  for I=1:B
      BSAMP=TNSPEC(PICKS(I,:),:);
      BTRAIN(I,:)=sum(BSAMP)/N;
  end
  BTRAIN;
  CNTER=sum(BTRAIN)/B;