GF
GF R -- make a Galois field from a quotient ring R which happens
to be isomorphic to a finite field.
GF(p,n) -- make a Galois field with p^n elements, where
p is a prime.
GF(q) -- make a Galois field with q elements, where
q is a power of a prime.
Options:
See also GaloisField.
