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Problems with named patterns

• To: mathgroup at christensen.cybernetics.net
• Subject: [mg1107] Problems with named patterns
• From: steve at tweedledee.ucsb.edu (Steve Trainoff)
• Date: Sun, 14 May 1995 23:51:40 -0400
• Organization: University of California, Santa Barbara

I am having a problem naming patterns using the syntax "x:pattern".
Here is a contrived example.

Mathematica 2.0 for NeXT
Copyright 1988-91 Wolfram Research, Inc.

(* Without an name this matches *)
In[1]:= a Cos[2 x] Cos[3 x] /. (Cos[n_. x_] Cos[m_. x_]) -> junk

Out[1]= a junk

(* With a name, but without a leading constant, this matches *)
In[2]:= Cos[2 x] Cos[3 x] /. q:(Cos[n_. x_] Cos[m_. x_]) -> junk

Out[2]= junk

(* With a name and a leading constant, this FAILS *)
In[3]:= a Cos[2 x] Cos[3 x] /. q:(Cos[n_. x_] Cos[m_. x_]) -> junk

Out[3]= a Cos[2 x] Cos[3 x]

What is going on here?

--

..STeve
------------------------------------
Insert pithy maxim here...
steve at tweedledee.ucsb.edu (NeXT mail)