Re: question: re-organising equations

*To*: mathgroup at smc.vnet.net*Subject*: [mg55264] Re: [mg55179] question: re-organising equations*From*: yehuda ben-shimol <bsyehuda at gmail.com>*Date*: Thu, 17 Mar 2005 03:31:34 -0500 (EST)*References*: <200503161035.FAA23761@smc.vnet.net>*Reply-to*: yehuda ben-shimol <bsyehuda at gmail.com>*Sender*: owner-wri-mathgroup at wolfram.com

First, note that in Mathematica notation you should use x==f[A,B,C,D] to define an equaltiy (unless you work with TradidionalForm) So I will use that notation here. you can use pattern matching myRule = {x -> A, y -> B, z -> C, w -> D, A -> x, B -> y, C -> z, D -> w} x==f[A,B,C,D]/.myRule will yield A == f[x, y, z, w] as desired yehuda On Wed, 16 Mar 2005 05:35:54 -0500 (EST), OneTel <david.hanson at student.unsw.edu.au> wrote: > > > I have a set of simultaneous equations which are very long and so I will > not include them here. They take the form of: > > x = f(A,B,C,D) > y = f(A,B,C,D) > z = f(A,B,C,D) > w = f(A,B,C,D) > > I would like to re-organise these into the form: > > A = f(x,y,z,w) > B = f(x,y,z,w) > C = f(x,y,z,w) > D = f(x,y,z,w) > > May I trouble you for some suggestions as to how this can be achieved? > > Thank you, > > David Hanson > Research Postgraduate > UNSW, Kensington 2052 NSW > >

**References**:**question: re-organising equations***From:*"OneTel" <david.hanson@student.unsw.edu.au>