Representative( D )
Representative returns a representative of the domain D.
The existence of a representative, and the exact definition of what a representative is, depends on the category of D. The representative should be an element that, within a given context, identifies the domain D. For example if D is a cyclic group, its representative would be a generator of D, or if D is a coset, its representative would be an arbitrary element of the coset.
Representative is pretty free in choosing a representative if
there are several. It is not even guaranteed that
returns the same representative if it is called several times for one
domain. Thus the main difference between
(see Random) is that
Representative is free to choose a value that is
cheap to compute, while
Random must make an effort to randomly
distribute its answers.
gap> C := Coset( Subgroup( G, [(1,4)(2,5)(3,6)] ), (1,6,5,4,3,2) );; gap> Representative( C ); (1,3,5)(2,4,6)
Representative first tests whether the component
is bound. If the field is bound it returns its value. Otherwise it
D.operations.Representative( D ), remembers the returned
D.representative, and returns it.
The default function called this way is
simply signals an error, since there is no default way to find a
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