> > I think we should rather represent series as a Series class, roughly > equivalent to SeriesData in Mathematica: > > http://reference.wolfram.com/mathematica/ref/SeriesData.html<http://www.google.com/url?q=http%3A%2F%2Freference.wolfram.com%2Fmathematica%2Fref%2FSeriesData.html&sa=D&sntz=1&usg=AFQjCNGUrewTF7qnSvMywwXBrTqnr9qneg> > >
This is a bit undocumented (as all in Mathematica, usually). For example, it's not so clear what kind of coefficients are allowed. > The Series class would interact with SymPy similar to how Poly works in > SymPy. > The Series would represent a series expansion in one variable (I don't > have opinions about multiple variables yet), so it would remember the > terms in some suitable format (see below, just like for Polys, there > are more options on the internal representation) and the order of the > series. Then, when you print it, it will print it just like we > currently do, with the "O(x^2)" term, though that's just how it is > printed. > Not sure if this is a Series class job. I mean, to remember terms. The Series should be build on (or to be itself) the ground of some stream-like entity, that can do actual arithmetic. Memoization/caching - another issue. > If you look at how GiNaC does it > It looks, like it can only formal power series and laurent (just like sage?). We want more? Open ideas: > > * I don't like that Order requires special handling in Add: > > https://github.com/sympy/sympy/blob/master/sympy/core/add.py#L237<https://www.google.com/url?q=https%3A%2F%2Fgithub.com%2Fsympy%2Fsympy%2Fblob%2Fmaster%2Fsympy%2Fcore%2Fadd.py%23L237&sa=D&sntz=1&usg=AFQjCNFg_9hCCBrkVjHKxInryZlS4ADe6g> > > That's another issue. But arithmetics (not differential calculus!) with O makes sense. -- 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. For more options, visit https://groups.google.com/groups/opt_out.
