2.12 IsSymmetric

IsSymmetric( rel )

IsSymmetric returns true if the binary relation rel is symnmetric and false otherwise.

    gap> IsSymmetric( Relation( [ [ 1 ], [ 1, 2 ], [ 1, 2, 3 ] ] ) );
    false
    gap> IsSymmetric( Relation( [ [ 2, 3 ], [ 1, 3 ], [ 1, 2 ] ] ) );
    true 

A relation R subseteq {1, ..., n} x {1, ..., n} is symmetric if (y, x) in R for all (x, y) in R. (See also SymmetricClosure.)

   
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