> > I did think about this... One would then have to find gcd's between > all pairs of (non-prime) factors which would get expensive very > quickly compared to a single gcd of the product.
I am not sure this is so clear cut in general. But since your example is in a sense the worst possible case, probably no algorithm can improve on taking gcd's after every step. > I do have > to say I am wary of including something (by default at least) that > can give a 10x speedup in some cases and 1000x slowdown in others. > Well there seems to be a misunderstanding. I want to repeat that I never wanted this to be enabled by default. I want to give the FractionField factory method an optional parameter 'cache' which when True would return an instance of FractionField_cache instead of FractionField_generic. The documentation would explain what are the benefits and pitfalls of this option. Your example is perfectly good for that. Michel Michel --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/ -~----------~----~----~----~------~----~------~--~---
