get_pairs_undir

 [Input] 
   C : undirected connectivity matrix 
 [Output] 
   pairs_bi : 1st and 2nd column -> two vertex points of an edge, 3rd
                 column -> connectivity label  1 = bi, 0 = uni.

 [Example] 
   pairs    = [1 2
               1 3]
 means un-directed connectivity between (1,2) and (1,3)

 Copyright (C) 2011, ATR All Rights Reserved.
 License : New BSD License(see VBMEG_LICENSE.txt)

0001 function pairs = get_pairs_undir(C)
0002 %
0003 % [Input]
0004 %   C : undirected connectivity matrix
0005 % [Output]
0006 %   pairs_bi : 1st and 2nd column -> two vertex points of an edge, 3rd
0007 %                 column -> connectivity label  1 = bi, 0 = uni.
0008 %
0009 % [Example]
0010 %   pairs    = [1 2
0011 %               1 3]
0012 % means un-directed connectivity between (1,2) and (1,3)
0013 %
0014 % Copyright (C) 2011, ATR All Rights Reserved.
0015 % License : New BSD License(see VBMEG_LICENSE.txt)
0016 
0017 C = triu(C,1); % upper diagonal components
0018 [I,J]=find(C ~= 0);
0019 pairs =[I J];
0020