function pajek(adj_mat,n,filename)

    fid = fopen(filename,'w');
 %   fid2 = fopen('satis.clu','w');
    fprintf(fid, '*Vertices %d\n',n);
 %   fprintf(fid2, '*Vertices %d\n',n);
 %   fid2 = fopen('labels_puc.clu', 'w');
    
      
    for i=1:n
       affil = char(subjects(sub_sort(i)).my_affil);
       if strmatch(affil, 'mlgrad')
			token = 1;
            shape = 'triangle';
            color = 'Red';
       elseif strmatch(affil, 'sloan')
           token = 2;
           shape = 'circle';
           color = 'Blue';

       elseif strmatch(affil, '1styeargrad ')
           token = 3;
           shape = 'diamond';
           color = 'Orange';
       else
           token = 4;
           shape = 'box';
           color = 'White';    
       end
       
       
       fprintf(fid,'%d "%s" %s x_fact 1.5 y_fact 1.5 ic %s\n',i, affil, shape, color);
 
 %        fprintf(fid,'%d *%s*\n',i, char(survey_txt(find(==(subjects(i)))+offset, 13)));
 %       fprintf(fid2,'%d\n', token);
 %       fprintf(fid2,'%d\n',sat_support(i));
        
  %      i=i+1;
    end
    
    fprintf(fid, '*Arcs\n');
    %fprintf(fid, '*Edges\n');
    
    for i=1:n
        for j=1:n
            if adj_mat(i,j)>0 % arbitrary threshold
                fprintf(fid, '%d   %d   %d\n',i,j,adj_mat(i,j));
            end
        end
    end    
    
    fclose(fid);
  % fclose(fid2);