GAP Manual: 18.4. IsFFE

IsFFE( obj )

IsFFE returns true if obj, which may be an object of an arbitrary type, is an element in a finite field and false otherwise. Will signal an error if obj is an unbound variable.

Note that integers, even though they can be multiplied with elements in finite fields, are not considered themselves elements in finite fields. Therefore IsFFE will return false for integer arguments.

    gap> IsFFE( Z(2^4)^7 );
    true
    gap> IsFFE( 5 );
    false