Re: Pattern Matching for Exponentials

*To*: mathgroup at smc.vnet.net*Subject*: [mg67503] Re: Pattern Matching for Exponentials*From*: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>*Date*: Thu, 29 Jun 2006 00:08:59 -0400 (EDT)*Organization*: The Open University, Milton Keynes, UK*References*: <e7tejf$444$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Rick Eller wrote: > I am looking for a pattern-matching replacement rule which will > transform exponential functions of the form exp(n i t) into > (1/(n^2-1))exp(n i t) where i = sqrt[-1]. For example, exp(2 i t) > should convert to (1/3)exp(2 i t). I've tried the following code without > success : > > In: Exp[2 i t] /. Exp[n_ i t] -> Exp[n i t]/(n^2-1) > > Out: e^2 i t > > I would appreciate any suggestions as to how this code should be > modified. > > Thanks, > > Rick Eller > Hi Rick, Well, I do not know what to say since that works fine on my system: In[1]:= Exp[2*i*t] Out[1]= 2 i t E In[2]:= FullForm[%] Out[2]//FullForm= Power[E, Times[2, i, t]] In[3]:= MatchQ[Exp[2*i*t], Exp[(n_)*i*t]] Out[3]= True In[4]:= Exp[2*i*t] /. Exp[(n_)*i*t] -> 0 Out[4]= 0 In[5]:= Exp[2*i*t] /. Exp[(n_)*i*t] -> Exp[n*i*t]/(n^(2) - 1) Out[5]= 1 2 i t - E 3 In[6]:= $Version Out[6]= 5.2 for Microsoft Windows (June 20, 2005) HTH, Jean-Marc