Replacement?

*To*: mathgroup at yoda.physics.unc.edu*Subject*: Replacement?*From*: francis at osiris.ucsd.edu (Francis)*Date*: Thu, 22 Apr 93 03:53:16 PDT

This may be a FAQ so apologies in advance. Help. I don't know what I'm doing wrong here. I simply want Mma to replace N q with Q everywhere mathematically possible, so that N^2 q^2 would be replaced by Q^2, N^3 q^2 by N Q^2 and so on. I tried the below but it didn't work and I'm not sure where I went wrong. My guess is that N q and N^2 q^2 "look" different to Mma so it doesn't touch it. But of course, N N q q is replaced by Q^2. Any help would be appreciated. Thanks in advance. *** Mathematica 2.1 for SPARC Copyright 1988-92 Wolfram Research, Inc. -- Athena graphics initialized -- In[1]:= Unprotect[Times] Out[1]= {Times} In[2]:= Unprotect[Power] Out[2]= {Power} In[3]:= N q = Q Out[3]= Q In[4]:= test = Simplify[N^2 q^2] 2 2 Out[4]= N q In[5]:= test2 = N^2 q^2 /. N q -> Q 2 2 Out[5]= N q In[6]:= test3 = Simplify[N^2 q^2]/.N q -> Q 2 2 Out[6]= N q In[7]:= test4 = Simplify[N^2 q^2 /. N q -> Q] 2 2 Out[7]= N q