(a) Currently in Macaulay2, fractions over quotients of polynomial rings do not have a nice normal form. In particular, sometimes the fractions are ’simplified’ to give much nastier looking fractions. We hope that in the near future, this misfeature will be corrected. (b) If you want to control the computation of the integral closure via optional arguments, then make sure you call
integralClosure(Ring) first, since
icFractions does not have optional arguments.