IsAffineCode( code )
IsAffineCode returns true if code is an affine code.
A code is called em affine if it is an affine space.
In other words, a code is affine if it is a coset of a linear code.
gap> IsAffineCode( HammingCode( 3, GF(2) ) );
true
gap> IsAffineCode( CosetCode( HammingCode( 3, GF(2) ),
> [ 1, 0, 0, 0, 0, 0, 0 ] ) );
true
gap> IsAffineCode( NordstromRobinsonCode() );
false
GAP 3.4.4