Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2004
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2004

[Date Index] [Thread Index] [Author Index]

Search the Archive

Named Patterns in Switch

  • To: mathgroup at smc.vnet.net
  • Subject: [mg48945] Named Patterns in Switch
  • From: "David Park" <djmp at earthlink.net>
  • Date: Thu, 24 Jun 2004 05:36:29 -0400 (EDT)
  • Sender: owner-wri-mathgroup at wolfram.com

Dear MathGroup,

Here is an attempted routine using Switch that does not work.

foo[expr_] :=
 Switch[expr,
        (a_.)*x^(n_), a,
        (a_.)*y^(n_), n]

foo[3*x^3]
a			(I was hoping for 3)


Switch uses patterns, but any named patterns are useless. So the a in the third argument in Switch has nothing to do with the a_. in the second argument.

Is there some Mathematica construction that will test successive patterns with names, do a calculation with the first match and use the names in the patterns?

David Park
djmp at earthlink.net
http://home.earthlink.net/~djmp/ 




  • Prev by Date: Re: faster sublist checking
  • Next by Date: Re: basic question about plotting 2 functions in one graph
  • Previous by thread: Periodic Table of Elements (Chemistry)
  • Next by thread: Re: Named Patterns in Switch