MathGroup Archive 2005

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

Search the Archive

Re: Transformation rule problem

  • To: mathgroup at smc.vnet.net
  • Subject: [mg58085] Re: [mg58041] Transformation rule problem
  • From: Bob Hanlon <hanlonr at cox.net>
  • Date: Fri, 17 Jun 2005 07:09:33 -0400 (EDT)
  • Reply-to: hanlonr at cox.net
  • Sender: owner-wri-mathgroup at wolfram.com

expr=a^2 b^4+a^3 b+a^5+a^5 b;

expr/.a^m_.*b^n_.:>
    (a^m*b^n*(d/a/b)^Min[m,n])

a^5 + d*a^4 + d*a^2 + b^2*d^2


Bob Hanlon

> 
> From: Oliver Buerschaper <groo137vy at yahoo.co.uk>
To: mathgroup at smc.vnet.net
> Date: 2005/06/16 Thu AM 07:19:35 EDT
> Subject: [mg58085] [mg58041] Transformation rule problem
> 
> Hi there,
> 
> I'm stuck with a problem concerning transformation rules and was 
> wondering whether somebody could give me a hint on this. I wouldn't 
> mind a complete solution either ;-) Here's the problem:
> 
> In a sum like for example
> 
> a^2 b^4 + a^3 b + a^5 + a^5 b
> 
> I'd like to replace every instance of the product (a b) by a different 
> expression, let's call it d. Thus my result should look like
> 
> d^2 b^2 + a^2 d + a^5 + a^4 d
> 
> This replacement is required to work for arbitrary a and b (especially 
> when they're functions). I've already tried some simple transformation 
> rules but they couldn't do the job.
> 
> Cheerio,
> Oliver
> 
> 


  • Prev by Date: Re: Mathematica 5.0 eps generation
  • Next by Date: Re: For Loop and Array related
  • Previous by thread: Re: Transformation rule problem
  • Next by thread: Re: Transformation rule problem