On Apr 23, 2009, at 4:07 PM, William Stein wrote:
> > Could you explain how assumptions are so important? Could you > particularly address how they can (1) be so critically important, and > yet (2) ginac doesn't have them. Incidentaly, to me they are > particularly important in symbolic integration, which ginac doesn't > do. Also, could you explain why the assumption system in Sympy > needs to be rewritten -- in particular, what design decisions were > suboptimal? > > -- William > One place where I use assumptions regularly is with trig functions. If you have sin(n*pi) or cos(n*pi), stating the assumption that n is integer reduces the first to 0 and the second to alternating +1,-1. These crop up in modal analysis of physical systems regularly. I don't know if sympy's assumptions are suboptimal, since I haven't used sympy much, but I guess it is since they're planning on improvements. Cheers, Tim. --- Tim Lahey PhD Candidate, Systems Design Engineering University of Waterloo http://www.linkedin.com/in/timlahey --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to sage-devel-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
