Hi, Thanks Brian and Ondrej, I have rencetly updated and uploaded my application.
On 04/07/2011 09:16 PM, Ondrej Certik wrote: > Yes. I assume some things will get faster? Which ones? Factorization, > or maybe integration? I don't exactly know which algorithms depend on > Groebner basis. Yes, this is the idea. I don't know about factorization but Aaron has suggested an application to integration of rational functions. SymPy uses Gröbner bases for, among other things (? I just grepped groebner...), solving systems of polynomial equations (solvers/polysys.py), computing minimal polynomials of algebraic numbers and computations in polynomial rings (gcd, lcm). For some tasks SymPy's current algorithm is quite slow, for example if you want to compute (by hand) the minimal polynomial of (x**2+y)/(x+y) where x is a root of X**3+X+1 and y is a root of Y**2+Y+1, you can compute the Gröbner basis of L=[x**3+x+1, y**2+y+1, (x+y)*z-(x**2+y)] with the lexicographic term order, i.e. >>> groebner(L, x, y, z, order="lex") I haven't let it finish in SymPy (after some 5-10 minutes). In SAGE this takes no time. (Interestingly, if you use order="grevlex", it becomes much faster but unusable for the purpose. I've added the Gröbner Walk algorithm to my application as an optional task if I have too much time left. Using it, the desired result can be obtained relatively cheap if I understand it correctly.) > In any case, also upload (if you didn't do so already) the application > to google-melange.com. It's a good start. I did. Any word on schedule would be much appreciated. I'm terrible at estimating such things. > Ondrej Jeremias -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
