I'm not very knowledgeable on this part of SymPy though. Hopefully I am wrong.
On Wed, Nov 14, 2012 at 2:01 PM, Matthew Rocklin <[email protected]> wrote: > My understanding is that SymPy is not able to handle information like > `assume(A<B)`. This has been on our issues list for a while I think. > > > On Wed, Nov 14, 2012 at 1:58 PM, Simon Clift <[email protected]> wrote: > >> Digging. I'm looking to hack something in to support symbolic intervals >> and need some advice, please. >> >> I'm getting my problem laid out as an intersection, but I'm hitting a >> problem performing the calculation symbolically. If I have >> >> A,B,C,D = symbols( ( "A", "B", "C", "D" ), real=True ) >> >> i_ab = Interval ( A, B ) >> i_cd = Interval ( C, D ) >> >> i_chk = Intersection( i_ab, i_cd ) >> >> then in line 449 of core/sets.py I don't have the is_comparable >> property. I was looking through the core/relational.py code for an >> operator that would allow me to impose a strict ordering, say A < C < B < D >> (in Maple I would use something like assume(A<B) ). Is there an accepted >> way of attaching an is_comparable type operation to the individual Symbol >> objects, say: >> >> A.is_lessthan( C ) >> >> which would (say) set >> >> A.is_comparable = True >> A.comparison_dict = { C : '<' } >> >> or something suitably Sympy-compatible? Should I fear combinatoric >> complexity problems evaluating that? >> >> Thanks >> -- Simon >> >> >> On Monday, 12 November 2012 15:15:52 UTC-5, Matthew wrote: >>> >>> If you do go digging around in the code I'd probably suggest working >>> with sympy.core.sets rather than sympy.stats. sympy.core.sets is better >>> organized and has a much lower entry barrier. >>> >> -- >> You received this message because you are subscribed to the Google Groups >> "sympy" group. >> To view this discussion on the web visit >> https://groups.google.com/d/msg/sympy/-/X8YHtVh_nJcJ. >> >> 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. >> > > -- 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.
