Hi Tim, On 11 Feb., 08:06, daly <d...@axiom-developer.org> wrote: > ... > Can you suggest an algorithm to implement this? > Is there an agreed-upon answer (i.e., not 42?)
Well, I had the impression that a couple of people are in favour of the following: gcd(a/b,c/d) := gcd(a,c)/lcm(b,d) lcm(a/b,c/d) := lcm(a,c)/gcd(b,d) It seems that this definition is already used in Maxima: sage: a=maxima(3/4) sage: b=maxima(5/6) sage: gcd(a,b) 1/12 Moreover, as one can easily see, the property gcd(x,y)*lcm(x,y)=x*y is preserved by that definition. In addition, if F is the fraction field of R and a,b are elements of R, then gcd(F(a),F(b))==gcd(a,b) and lcm(F(a),F(b))==lcm(a,b). So, that's the rationale. Best regards, Simon -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
