Re: Symbolic Derivatives of Unspecified Functions
- To: mathgroup at smc.vnet.net
- Subject: [mg70732] Re: Symbolic Derivatives of Unspecified Functions
- From: David Bailey <dave at Remove_Thisdbailey.co.uk>
- Date: Wed, 25 Oct 2006 01:39:58 -0400 (EDT)
- References: <ehf1mp$5e9$1@smc.vnet.net> <ehhqlj$7cm$1@smc.vnet.net> <ehkc7f$hjf$1@smc.vnet.net>
Hello, A definition such as r[qi_,qj_]:=r[qi,qj] (or the equivalent using =) is meaningless - it simply defines r in terms of itself - this sends Mathematica into a spin, which produces your iteration limit error. I am sorry if you thought I was suggesting this - I was merely quoting a bit of your original message! The crucial thing to understand is that you can differentiate a function (or use it in other ways) without providing any definition at all - this is the appropriate thing to do. David Bailey http://www.dbaileyconsultancy.co.uk