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(GF(2),6,order='invlex') I = R.ideal([ mynumerator((ud1*(ux1+uy1)+ud2*(ux1^2+uy1^2))-((ux1+ux1^2)*(uy1+uy1^2))) , mynumerator((ud1*(ux2+uy2)+ud2*(ux2^2+uy2^2))-((ux2+ux2^2)*(uy2+uy2^2))) ]) J = I + R.ideal([0 , ux1-ux2 , uy1-uy2 ]) ud1 = fastfrac(ud1) ud2 = fastfrac(ud2) ux1 = fastfrac(ux1) uy1 = fastfrac(uy1) ux2 = fastfrac(ux2) uy2 = fastfrac(uy2) ux3 = (((ud1*(ux1+ux2)+ud2*(ux1+uy1)*(ux2+uy2)+(ux1+ux1^2)*(ux2*(uy1+uy2+fastfrac(1))+uy1*uy2))/(ud1+(ux1+ux1^2)*(ux2+uy2)))).reduce() uy3 = (((ud1*(uy1+uy2)+ud2*(ux1+uy1)*(ux2+uy2)+(uy1+uy1^2)*(uy2*(ux1+ux2+fastfrac(1))+ux1*ux2))/(ud1+(uy1+uy1^2)*(ux2+uy2)))).reduce() ux4 = (((ud1*(ux1+ux1)+ud2*(ux1+uy1)*(ux1+uy1)+(ux1+ux1^2)*(ux1*(uy1+uy1+fastfrac(1))+uy1*uy1))/(ud1+(ux1+ux1^2)*(ux1+uy1)))).reduce() uy4 = (((ud1*(uy1+uy1)+ud2*(ux1+uy1)*(ux1+uy1)+(uy1+uy1^2)*(uy1*(ux1+ux1+fastfrac(1))+ux1*ux1))/(ud1+(uy1+uy1^2)*(ux1+uy1)))).reduce() a0 = fastfrac((fastfrac(1))) a1 = fastfrac((fastfrac(1))) a2 = fastfrac((ud1^2+ud2)) a3 = fastfrac((fastfrac(0))) a4 = fastfrac((fastfrac(0))) a6 = fastfrac((ud1^4*(ud1^4+ud1^2+ud2^2))) wu1 = ((ud1*(ud1^2+ud1+ud2)*(ux1+uy1)/(ux1*uy1+ud1*(ux1+uy1)))).reduce().sreduce() wv1 = ((ud1*(ud1^2+ud1+ud2)*(ux1/(ux1*uy1+ud1*(ux1+uy1))+ud1+fastfrac(1)))).reduce().sreduce() print isidentity(a0*(wv1^2)+a1*(wu1*wv1)+a3*wv1-(((wu1+a2)*wu1+a4)*wu1+a6)) print isidentity(ux1-(ud1*(wu1+ud1^2+ud1+ud2)/(wu1+wv1+(ud1^2+ud1)*(ud1^2+ud1+ud2)))) print isidentity(uy1-(ud1*(wu1+ud1^2+ud1+ud2)/(wv1+(ud1^2+ud1)*(ud1^2+ud1+ud2)))) wu2 = ((ud1*(ud1^2+ud1+ud2)*(ux2+uy2)/(ux2*uy2+ud1*(ux2+uy2)))).reduce().sreduce() wv2 = ((ud1*(ud1^2+ud1+ud2)*(ux2/(ux2*uy2+ud1*(ux2+uy2))+ud1+fastfrac(1)))).reduce().sreduce() wu3 = ((ud1*(ud1^2+ud1+ud2)*(ux3+uy3)/(ux3*uy3+ud1*(ux3+uy3)))).reduce().sreduce() wv3 = ((ud1*(ud1^2+ud1+ud2)*(ux3/(ux3*uy3+ud1*(ux3+uy3))+ud1+fastfrac(1)))).reduce().sreduce() wu4 = ((ud1*(ud1^2+ud1+ud2)*(ux4+uy4)/(ux4*uy4+ud1*(ux4+uy4)))).reduce().sreduce() wv4 = ((ud1*(ud1^2+ud1+ud2)*(ux4/(ux4*uy4+ud1*(ux4+uy4))+ud1+fastfrac(1)))).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)