On Wednesday, January 21, 2015 at 8:12:31 PM UTC+1, [email protected] wrote: > > Hi Francesco, > > I'm sorry for my long latency time. > > Concerning a Lie algebra defined by the structure constants: keep in mind >> this is a way often used in Physics, which is not very rigorous. Structure >> constants define an equivalence class of bases in a Lie algebra. >> >> For example, consider a Lie algebra with two generators: *A, B*. If you >> define *X = 2*A - 3*B, Y = A + B*, then *X *and *Y* are still >> generators, but will have generally different structure constants. >> > > Yes, that is clear to me. Maybe the documentation is too imprecise at this > point. Unfortunately a "real" Lie-Algebra class makes (except in the > semisimple case) no sense, because the classification of Lie-Algebras is > really a non-trivial problem. You may have a look on the method > > GLV_Action(self, a): #Computes the Action of an Element of GL(V) on the > Variety of Structure Constants >
By the way, there is already some support for Lie algebras in SymPy: https://github.com/sympy/sympy/tree/998a9100f3c8493a2b6f1ff10c02024f36d48811/sympy/liealgebras Have a look at this. It does not depend on numpy. Also notice where the tests are placed. > Due to your other remarks, I will revise my code promptly. > > Actually, those remarks are necessary if you want your objects to be part of a SymPy expression tree. There are some exceptions in SymPy where classes do not inherit from Basic, but those objects are not meant to be part of the expression tree. Concerning the style, usually in SymPy class names use CamelCase, while methods and functions use snake_case. -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/239c3826-c4cc-41c2-a7d5-d936363a630d%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
