StarCyc( z )
If z is an irrational element of a quadratic number field (i.e. if
z is a quadratic irrationality), StarCyc( z )
returns the unique
Galois conjugate of z that is different from z; this is often
called <z>ast (see DisplayCharTable). Otherwise false
is
returned.
gap> StarCyc( EB(5) ); StarCyc( E(5) ); E(5)^2+E(5)^3 false
GAP 3.4.4