> > For what is worth, I also wrote a wick expansion in sympy, see my > "wick" branch at github: > > http://github.com/certik/sympy/tree/wick > > if you run the "t.py" script in the root directory, it will save all > the feynman diagrams to /tmp as png images. It only works for scalar > bosons.
Your wicks code looks fast, but I'm not sure if a similar approach could be used for Fermions. You need to take into account the order of the operators, so a dict is not that useful. Except, maybe we could try a two-step computation and use dicts to quickly determine which operators are candidates for nonzero contractions. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sympy-patches" group. To post to this group, send email to sympy-patches@googlegroups.com To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en -~----------~----~----~----~------~----~------~--~---
