On Sep 28, 3:09 pm, Tim Lahey <tim.la...@gmail.com> wrote: > The D notation is used in Maple as an option, but almost always allows > conversion to the standard notation.
OK, this thread should probably go to sage-devel or elsewhere, but I don't know how to do that. Maple actually falls back on exactly the same D notation (but the index more comfortably 1-based rather than 0- based) in more complicated cases. Example in Maple: > lprint(diff(f(g(u,v,w),y,z),u)); D[1](f)(g(u,v,w),y,z)*diff(g(u,v,w),u) > lprint(diff(f(u+v,u-v),u)); D[1](f)(u+v,u-v)+D[2](f)(u+v,u-v) > lprint(diff(f(x+6),x,x,x,x)); `@@`(D,4)(f)(x+6) So maple seems to prefer "diff" if there is an obvious variable name available, but doesn't go out of its way to invent auxiliary variable names. Instead it uses D[1]. Comparing this to sage: sage: var("x y z u v w") sage: f=function('f') sage: g=function('g') sage: diff(f(g(u,v,w),y,z),u) D[0](f)(g(u, v, w), y, z)*D[0](g)(u, v, w) sage: diff(f(u+v,u-v),u) D[0](f)(u + v, u - v) + D[1](f)(u + v, u - v) sage: diff(f(x+6),x,x,x,x) D[0, 0, 0, 0](f)(x + 6) So it seems that sage only differs from maple in the most trivial case. --~--~---------~--~----~------------~-------~--~----~ 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 URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---