42.1 IsGeneralMapping

IsGeneralMapping( obj )

IsGeneralMapping returns true if the object obj is a mapping (possibly multi valued) and false otherwise.

    gap> g := Group( (1,2,3,4), (2,4), (5,6,7) );;  g.name := "g";;
    gap> p4 := MappingByFunction( g, g, x -> x^4 );
    MappingByFunction( g, g, function ( x )
        return x ^ 4;
    end )
    gap> IsGeneralMapping( p4 );
    true
    gap> IsGeneralMapping( InverseMapping( p4 ) );
    true    # note that the inverse mapping is multi valued
    gap> IsGeneralMapping( x -> x^4 );
    false    # a function is not a mapping 

See MappingByFunction for the definition of MappingByFunction and InverseMapping for InverseMapping.

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