There is definitely going to be some form of pattern matching, as it is pretty much required by simplification. The exact syntax isn't decided yet. 1) Everything has been converted to Cython and all of the internals are pure Cython with no or very few python function calls. The code is essentially pure, hand-tuned C. Even functions that use pexpect to have maxima do all of the work are twice as fast in many cases, and those that don't call maxima at all (which is the goal for all core-functionality) are hundreds or even thousands of times faster (if not more).
2) I agree. Expansion should happen before coefficient (if perhaps as an option). +1 3) This is consistent with the behavior of Mathematica and Maple, so +1 4) This seems like a pretty easy addon to base functionality. +1 On Thu, May 22, 2008 at 1:48 PM, Andrey Novoseltsev <[EMAIL PROTECTED]> wrote: > > Actually, yesterday was the first time I really tried to use Sage for > symbolic computations and it was quite frustrating for me. > > 1) It would be really nice if it was faster. > > 2) It seems to me that > ((x+y)*y).coeff(y^2) > and > ((x+y)*y).expand().coeff(y^2) > should return the same coefficient 1 (while the first one returns > zero). > > 3) I think that > ((x+x*y)/x).simplify() > should return 1+y, instead of the original expression, otherwise, what > is simplify simplifying? > > 4) It would be nice to be able to get the part of given degree in the > given list of variables, and write > f3 = fp.homogeneous_part([up, vp], 3) > instead of something like > f3 = (fp.coeff(up,3).coeff(vp,0)*up^3*vp^0 > + fp.coeff(up,2).coeff(vp,1)*up^2*vp^1 > + fp.coeff(up,1).coeff(vp,2)*up^1*vp^2 > + fp.coeff(up,0).coeff(vp,3)*up^0*vp^3) > > > --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com 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://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
