On Mon, Jul 23, 2012 at 9:17 PM, Aaron Meurer <[email protected]> wrote: > On Jul 23, 2012, at 2:20 AM, Sergiu Ivanov <[email protected]> wrote: > >> On Sun, Jul 22, 2012 at 11:44 PM, Aaron Meurer <[email protected]> wrote: >>> >>> Can you be more specific? Most likely, one of the results is "better" >>> than the other, and the algorithm should be fixed to always give it >>> regardless of ordering. >> >> FiniteSet._complement works as follows: >> >>>>> from sympy import FiniteSet >>>>> FiniteSet(1, 2, 3).complement >> (-oo, 1) U (1, 2) U (2, 3) U (3, oo) >> >> I'm not sure this result can be achieved more efficiently by a >> different approach then sorting the elements. > > This is the exact same as FiniteSet itself. Union's args do not need > to be sorted except within the printer.
I was referring to the fact that, for example, FiniteSet(3, 1, 2).complement should return the same result. In other words, to get the complement relative to RR, one has to sort the numbers in the FiniteSet first, because otherwise one may get stuff like (-oo, 3) U (1, 2) U (2, oo). I really hope my explanation is more or less clear. Sergiu -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
