10 equality tests fail on Rational Field %13 >> y2=coefficient(y1,0)::U F @ Boolean Comp: 0 msec, Interp: 10 msec %14 >> y2 1796821323 / 298728016 @ U Comp: 0 msec, Interp: 0 msec %15 >> coefficient(y1,0)::U 1796821323 / 298728016 @ U This is a case of two identical and similar members of the Aldor LibAlgebra's Fraction field testing false to equality. Equality in this case is exported by the Fraction domain. I have to fix this in the coming hours/days to move my work forward but this bug report might be useful. Filatei dk 1 Use interpreter to create a Fraction Field and perform = 1.0.2 afilatei@scl.csd.uwo.ca yes dk dk dk dk dk dk yes