Pattern Matching Problem
- To: mathgroup at smc.vnet.net
- Subject: [mg43377] Pattern Matching Problem
- From: "Ersek, Ted R" <ErsekTR at navair.navy.mil>
- Date: Wed, 27 Aug 2003 04:05:03 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Consider the following:
In[1]:=
ClearAll[f,a,b,c,w,x,y,z];
expr=a+b+c+f[w,2]+f[w,3]+x+f[x,2]+f[x,3]+y+f[y,2]+f[z,2];
Can somebody suggest a general way to seperate the terms above into like
groups. By "like" I mean having the same second argument for (f). So for
this example I want to get
{a+b+c+x+y, f[w,2]+f[x,2]+f[y,2]+f[z,2], f[w,3]+f[x,3]}
The pattern matcher should be able to do this because Plus has attributes
Flat and Orderless. However I can't find a way to make it happen.
-------------------
Thanks,
Ted Ersek