description:
g=NCcycEqRep(f) constructs a canonical cyclically equivalent representative of the polynomial f.
arguments:
f is an NCpoly representing a polynomial
output:
g is an NCpoly representing a polynomial which is cyclically equivalent to the polynomial f
possible usage:
NCcycEqRep(f)
example:
>> NCcycEqRep(x^2*y*x+y*x^3+x*y*x+x^2*y-2*y*x^2)
ans = 2*x^3*y