def mynumerator(x): if parent(x) == R: return x return numerator(x) class fastfrac: def __init__(self,top,bot=1): if parent(top) == ZZ or parent(top) == R: self.top = R(top) self.bot = R(bot) elif top.__class__ == fastfrac: self.top = top.top self.bot = top.bot * bot else: self.top = R(numerator(top)) self.bot = R(denominator(top)) * bot def reduce(self): return fastfrac(self.top / self.bot) def sreduce(self): return fastfrac(I.reduce(self.top),I.reduce(self.bot)) def iszero(self): return self.top in I and not (self.bot in I) def isdoublingzero(self): return self.top in J and not (self.bot in J) def __add__(self,other): if parent(other) == ZZ: return fastfrac(self.top + self.bot * other,self.bot) if other.__class__ == fastfrac: return fastfrac(self.top * other.bot + self.bot * other.top,self.bot * other.bot) return NotImplemented def __sub__(self,other): if parent(other) == ZZ: return fastfrac(self.top - self.bot * other,self.bot) if other.__class__ == fastfrac: return fastfrac(self.top * other.bot - self.bot * other.top,self.bot * other.bot) return NotImplemented def __neg__(self): return fastfrac(-self.top,self.bot) def __mul__(self,other): if parent(other) == ZZ: return fastfrac(self.top * other,self.bot) if other.__class__ == fastfrac: return fastfrac(self.top * other.top,self.bot * other.bot) return NotImplemented def __rmul__(self,other): return self.__mul__(other) def __div__(self,other): if parent(other) == ZZ: return fastfrac(self.top,self.bot * other) if other.__class__ == fastfrac: return fastfrac(self.top * other.bot,self.bot * other.top) return NotImplemented def __pow__(self,other): if parent(other) == ZZ: return fastfrac(self.top ^ other,self.bot ^ other) return NotImplemented def isidentity(x): return x.iszero() def isdoublingidentity(x): return x.isdoublingzero() R. = PolynomialRing(QQ,5,order='invlex') I = R.ideal([ mynumerator((ux1^3+uy1^3+1)-(3*ud*ux1*uy1)) , mynumerator((ux2^3+uy2^3+1)-(3*ud*ux2*uy2)) ]) J = I + R.ideal([0 , ux1-ux2 , uy1-uy2 ]) ud = fastfrac(ud) ux1 = fastfrac(ux1) uy1 = fastfrac(uy1) ux2 = fastfrac(ux2) uy2 = fastfrac(uy2) ux3 = (((uy1^2*ux2-uy2^2*ux1)/(ux2*uy2-ux1*uy1))).reduce() uy3 = (((ux1^2*uy2-ux2^2*uy1)/(ux2*uy2-ux1*uy1))).reduce() ux4 = ((uy1*(fastfrac(1)-ux1^3)/(ux1^3-uy1^3))).reduce() uy4 = ((ux1*(uy1^3-fastfrac(1))/(ux1^3-uy1^3))).reduce() a0 = fastfrac((fastfrac(1))) a1 = fastfrac((fastfrac(0))) a2 = fastfrac((fastfrac(0))) a3 = fastfrac((fastfrac(0))) a4 = fastfrac((-fastfrac(27)*ud*(ud^3+fastfrac(8)))) a6 = fastfrac((fastfrac(54)*(ud^6-fastfrac(20)*ud^3-fastfrac(8)))) wu1 = ((fastfrac(12)*(ud^3-fastfrac(1))/(ud+ux1+uy1)-fastfrac(9)*ud^2)).reduce().sreduce() wv1 = ((fastfrac(36)*(uy1-ux1)*(ud^3-fastfrac(1))/(ud+ux1+uy1))).reduce().sreduce() print isidentity(a0*(wv1^2)+a1*(wu1*wv1)+a3*wv1-(((wu1+a2)*wu1+a4)*wu1+a6)) print isidentity(ux1-((fastfrac(36)*(ud^3-fastfrac(1))-wv1)/(fastfrac(6)*(wu1+fastfrac(9)*ud^2))-ud/fastfrac(2))) print isidentity(uy1-((wv1+fastfrac(36)*(ud^3-fastfrac(1)))/(fastfrac(6)*(wu1+fastfrac(9)*ud^2))-ud/fastfrac(2))) wu2 = ((fastfrac(12)*(ud^3-fastfrac(1))/(ud+ux2+uy2)-fastfrac(9)*ud^2)).reduce().sreduce() wv2 = ((fastfrac(36)*(uy2-ux2)*(ud^3-fastfrac(1))/(ud+ux2+uy2))).reduce().sreduce() wu3 = ((fastfrac(12)*(ud^3-fastfrac(1))/(ud+ux3+uy3)-fastfrac(9)*ud^2)).reduce().sreduce() wv3 = ((fastfrac(36)*(uy3-ux3)*(ud^3-fastfrac(1))/(ud+ux3+uy3))).reduce().sreduce() wu4 = ((fastfrac(12)*(ud^3-fastfrac(1))/(ud+ux4+uy4)-fastfrac(9)*ud^2)).reduce().sreduce() wv4 = ((fastfrac(36)*(uy4-ux4)*(ud^3-fastfrac(1))/(ud+ux4+uy4))).reduce().sreduce() slope = ((wv2-wv1)/(wu2-wu1)).reduce().sreduce() print isidentity(a0*slope^2+a1*slope-a2-wu1-wu2-wu3) print isidentity(slope*(wu1-wu3)-wv1-a1*wu3-a3-wv3) slope = ((fastfrac(3)*wu1^2+fastfrac(2)*a2*wu1+a4-a1*wv1)/(fastfrac(2)*a0*wv1+a1*wu1+a3)).reduce().sreduce() print isidentity(a0*slope^2+a1*slope-a2-wu1-wu1-wu4) print isidentity(slope*(wu1-wu4)-wv1-a1*wu4-a3-wv4)