On Nov 4, 2009, at 7:43 PM, wxu...@sohu.com wrote: > > Hi, all > > > I just saw that if I defined a function: f=f(e^t),
How did you define f? Perhaps > the f.diff(f,t) will give e^t*D[0](f)(e^t). and the > > question is what is the meaning of D[0](f)(e^t)? > > I can find that in the help of diff(). > > thanks in advance. D[0](f) means the derivative of f with respect to the 0th variable, i.e. in this case it just means f', so your answer is e^t * f'(e^t) There have been numerous discussions about reducing this confusing notation, but nothing has gotten in yet... - Robert --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
