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Posets :: removeIsomorphicPosets

removeIsomorphicPosets -- returns a sub-list of non-isomorphic posets

Synopsis

Description

This method returns a sublist N of L containing the elements of L, in order, where the first instance of each isomorphism class is retained.
i1 : L = {chain 4, divisorPoset (2^3), booleanLattice 3, booleanLattice 2, product(3, i -> chain 2)};
i2 : removeIsomorphicPosets L

o2 = {Poset{cache => CacheTable{...16...}        },
            GroundSet => {1, 2, 3, 4}              
            RelationMatrix => | 1 1 1 1 |          
                              | 0 1 1 1 |          
                              | 0 0 1 1 |          
                              | 0 0 0 1 |          
            Relations => {{1, 2}, {2, 3}, {3, 4}}  
                                                   
                                                   
                                                   
                                                   
     ------------------------------------------------------------------------
     Poset{cache => CacheTable{...13...}                                
           GroundSet => {000, 001, 010, 011, 100, 101, 110, 111}        
           RelationMatrix => | 1 1 1 1 1 1 1 1 |                        
                             | 0 1 0 1 0 1 0 1 |                        
                             | 0 0 1 1 0 0 1 1 |                        
                             | 0 0 0 1 0 0 0 1 |                        
                             | 0 0 0 0 1 1 1 1 |                        
                             | 0 0 0 0 0 1 0 1 |
                             | 0 0 0 0 0 0 1 1 |
                             | 0 0 0 0 0 0 0 1 |
           Relations => {{000, 001}, {010, 011}, {000, 010}, {001, 011},
     ------------------------------------------------------------------------
                                                                            
                                                                            
                                                                            
                                                                            
                                                                            
                                                                            
                                                                            



     {100, 101}, {110, 111}, {100, 110}, {101, 111}, {000, 100}, {001, 101},
     ------------------------------------------------------------------------
                            }, Poset{cache => CacheTable{...13...}         
                                     GroundSet => {00, 01, 10, 11}
                                     RelationMatrix => | 1 1 1 1 |
                                                       | 0 1 0 1 |
                                                       | 0 0 1 1 |
                                                       | 0 0 0 1 |
                                     Relations => {{00, 01}, {10, 11}, {00,



     {010, 110}, {011, 111}}
     ------------------------------------------------------------------------
                   }}





     10}, {01, 11}}

o2 : List
This method uses the method isomorphism, which was ported from John Stembridge’s Maple package available at http://www.math.lsa.umich.edu/~jrs/maple.html#posets.

See also

Ways to use removeIsomorphicPosets :