2009/6/5 Tim Lahey <[email protected]>: > > > On Jun 5, 2009, at 3:14 PM, Robert Bradshaw wrote: > >> >> On Jun 5, 2009, at 8:39 AM, Burcin Erocal wrote: >> >>> >>> On Fri, 5 Jun 2009 09:37:07 -0300 >>> Golam Mortuza Hossain <[email protected]> wrote: >>> >>>> >>> >>>> (3) symbolic "diff" now returns a rather incomprehensible output >>>> ------- >>>> f(x) = function('f',x) >>>> diff(f(x),x) >>>> D[0](f)(x) >>>> ------- >>>> What does that '0' really means? Typeset version also looks similar. >>> >>> This is also the notation used by Maple, we inherited it from GiNaC. >>> Here is some explanation from the Maple manual: >>> >>> http://www.maplesoft.com/support/help/view.aspx?path=D >>> >>> Indexes in Sage start from 0, not 1. I think this is the only >>> difference between Maple and Sage. >> >> I can see how this can be more powerful, but I have to admit I'm not >> a fan of this compared to the standard df/dx notation. >> >> - Robert > > I hate this notation in Maple, but it's pretty much optional. Plus, > while > I understand using 0-based indexing, the numbers have a particular > meaning > for derivatives, so 0 doesn't make sense for a first derivative. The 0th > derivative is the function.
Absolutely! We definitely cannot have the first derivative display as D[0]. John > > I'd like to use the standard derivative notation. > > 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 [email protected] 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 -~----------~----~----~----~------~----~------~--~---
