Forwarded to sage-support.
---------- Forwarded message ---------- From: storne...@mathisasport.com <storne...@mathisasport.com> Date: Fri, Jan 20, 2012 at 9:52 PM Subject: sagemath question re: implicit differentiation To: wdjoy...@gmail.com I apologize in advance if this is the wrong way to reach you, but at the bottom of this thread on implicit differentiation in sage: http://www.mail-archive.com/sage-support@googlegroups.com/msg04520.html it says reply via email to david joyner. Again, I'm new to the sage community, so perhaps this is the wrong way to ask the followup question, but here goes: I follow your comment, where you instruct the person on how to differentiate. As you know, however, in an implicit differentiation problem often we then went to solve for dy/dx. so, for example, I have this: sage: f = function('f',x) sage: f f(x) sage: equation2 = x*f + 2*f^2 == 1 sage: equation2.diff() x*D[0](f)(x) + 4*f(x)*D[0](f)(x) + f(x) == 0 That's fine, but now I want to solve for dy/dx, so I try: sage: solve(equation2.diff(),diff(f(x),x,1)) /home/stornetta/sage-4.7.2/local/lib/python2.6/site-packages/IPython/iplib.py:2260: DeprecationWarning: Substitution using function-call syntax and unnamed arguments is deprecated and will be removed from a future release of Sage; you can use named arguments instead, like EXPR(x=..., y=...) exec code_obj in self.user_global_ns, self.user_ns [D[0](f)(x) == -f(x)/(x + 4*f(x))] as you can see, I do get an answer, but the interpreter indicates my approach is deprecated, and I'm not clear on how one would use named arguments in this situation to achieve the same result. Any advice would be welcome, or if their is a forum that I should post to instead, again I apologize for troubling you directly, if you could just give me a pointer for where to post. -- W. Scott Stornetta, Ph.D. 973.944.0410 -- 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
