Re: Replace certain variable

*To*: mathgroup at smc.vnet.net*Subject*: [mg74833] Re: Replace certain variable*From*: jesse.woodroffe at gmail.com*Date*: Sat, 7 Apr 2007 04:03:45 -0400 (EDT)*References*: <ev51a7$a63$1@smc.vnet.net>

Although I suspect there may be even cleaner ways to do it, you could use a replacement rule such as F[w]*Exp[I*w*t]/.{Exp[g:(restOfExponent__*w)]->Exp[restOfExponent*(x +s*a)]} This rule works for any sequence of multiplications in the exponent, so long as w is somewhere and there actually IS a multiplication, i.e. it doesn't work for w alone. To remedy that situtation, you could also include a specific replacement for Exp[w], Exp[w]->Exp[x*s+a] This being said, I'd guess that there's a way that would get both cases at once. Jesse Woodroffe On Apr 6, 3:44 am, "KFUPM" <hussain.alqaht... at gmail.com> wrote: > Dear Group > > If i have a term like : F[w]*Exp[I*w*t] where F[w] is an arbitrary > function, and i want to replace w by x+ s*a only in the exponent not > in F[w], i wonder what is the quickest and easiest way to do it > provided that i have so many similar terms. > > Your help and prompt reply is highly appreciated. > > HMQ