> On Tue, Aug 26, 2008 at 9:15 AM, David Philp <[EMAIL PROTECTED]> wrote: >> >> >> On 26/08/2008, at 5:09 PM, Burcin Erocal wrote: >>> In[]:= Assuming[0<x, Assuming[x<Pi/2 ,ArcCos[Cos[x]]]] >>> Out[]= ArcCos[Cos[x]] >> >> In[]:= Simplify[ArcCos[Cos[x]], Assumptions -> 0 < x < Pi/2] >> Out[] = x > > Exactly, you pass the assumptions as an object to the simplify > function. That's the point, it's very explicit and what I like. > > I really need to learn mathematica and then just do the same, instead > of trying to do something and then burn myself.
Strong +1. At a bare minimum it is best to at least *understand* what Mathematica (and Maple and Giac/Maxima/Axiom, etc.) do, and then make choices justifying why you think you can do better, rather than starting from scratch. I am extremely appreciative that there are so many expert Mathematica/Maple/Giac/Maxima/Axiom, etc. users posting in this thread, since this is making our job of understanding what those systems do in various situations *vastly* easier. (In particular, notice how many mistakes some of us core sage devs make when making assertions about what Mathematica or Maxima or whatever does or can do. It's really awesome that users of those systems are regularly helping us out.) Thanks! > On Tue, Aug 26, 2008 at 9:06 AM, Fernando Perez <[EMAIL PROTECTED]> wrote: > Thanks Fernando for mentioning LPGL. Actually, in fact Kirill, another > sympy developer who works on the core of sympy a lot, he didn't have > time to advocate it yet, but he also very much like LGPL and always > wanted sympy to be LGPL to prevent code abuse. I don't think such code > abuse is actually happening though, so I think it's more of an > irrational fear, but I am in no way trying to make it invaluable > argument -- I may well be completely wrong on this. > > But did it ever happen to you Fernando that someone would plainly > abuse ipython/numpy/scipy? Clearly ipython is way more popular than > sympy, so if it doesn't happen for numpy/scipy/ipython, I don't think > we have to fear. (btw. fear of what actually?) Ah, to be young and idealistic. :-) > But as I said several times, I am not fundamental in this, if it helps > all the sympy developers to sleep well at night, let's do it. I am not > making fun of it, I mean it. It's simply not worhty if many people > feel that their code will be abused and it's not a question if, but > when. So this clearly has to be resolved in some way. My way is to > question this very fear itself, I suspect it's not happening this way. > The other option is to switch to LGPL or GPL. > > Burcin, would LGPL be suitable for you to contribute to sympy, or is > LGPL not protective enough for you? Since Burcin's whole proposal is to use GiNaC, I suspect that he is only going to write something if it builds on GiNaC. As GiNaC is GPL'd the above question might be moot, since it seems difficult to build an LGPL'd Sympy on top of GiNaC... -- William --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
