www.pudn.com > ConstrainedEM.zip > set_start_params3.m

%last modified by Tomer 22/6/02 14:13 
 
% set_start_params3 
dont_mark_nei_f=1;	% when set, only the seed point is removed from candidate list 
% 					for the next seeds. when not set, all the neighbourhood is removed. 
use_chunklet_info_f=0;	% when set , the centers are choosen after a chunklet closure 
%					operator has been applied to the neighbourhood. 
 
cluster_size=floor(n/k); 
used_flags=zeros(n,1); 
noise_param=1; 
%keyboard 
for j=1:k 
    % randomize cluster seed 
    seed_ind=floor(rand*(n-1))+1; 
    while used_flags(seed_ind)      % find unused seed 
        seed_ind=floor(rand*(n-1))+1; 
    end 
     
    if dont_rand_covmat_flag==1       % rand only centers 
        param{j,1}=data(seed_ind,:); 
        used_flags(seed_ind)=1; 
    else                              % rand centers and cov matrices 
        seed=data(seed_ind,:);  
         
        %find neighbourhood   
         
        dists=sum(((data-ones(n,1)*seed).^2)'); 
        [ tmp inds ]=sort( dists ); 
        number_of_nei=max(round(n/(k*noise_param)),d+1); 
        inds=inds(1:number_of_nei); 
         
        % include chunklet closure in the choosen neighbours 
        if (ch_num>0) & ( use_chunklet_info_f==1) 
            inds2=find (chunks(inds)~=-1); 
            c_inds=unique(chunks(inds(inds2))); % indexes of chunklets to add. 
            for jj=1:length(c_inds)      % adding the chunklets 
                inds=union(inds,find(chunks==c_inds(jj))); 
            end 
        end 
         
        if dont_mark_nei_f==1 
            used_flags(seed_ind)=1; 
        else 
            used_flags(inds)=1; 
        end 
         
        % set params 
        param{j,2}=cov(data(inds,:)); 
        param{j,1}=mean(data(inds,:)); 
    end 
end 
     
if (single_cov_mat_flag==1)&(dont_rand_covmat_flag==0) 
    % unify the cov matrixes ( mean them ) and put the result in param{1,2} 
    tmp=zeros(d,d); 
    for j=1:k 
        tmp=tmp + param{j,2}; 
    end 
    param{1,2}=tmp/k; 
    %clear all other cov mats!!!!! 
    for j=2:k 
      param{j,2}= []; 
    end 
     
end