Re: Common factors in a list
- To: mathgroup at smc.vnet.net
 - Subject: [mg58349] Re: Common factors in a list
 - From: dh <dh at metrohm.ch>
 - Date: Tue, 28 Jun 2005 21:56:46 -0400 (EDT)
 - References: <d9r50q$568$1@smc.vnet.net>
 - Sender: owner-wri-mathgroup at wolfram.com
 
Hi John,
you could try to create a polynomial in a new variable, say z, from your 
vector by:
v={a x, a y, a z};
pol=Table[z^i,{i,Length[v]}] . v
now you could extract a common factor by:
com= FactorTerms[pol,z][[1]]
the residual vector you get from:
v/com
sincerely, Daniel
John Reed wrote:
> I'm working with a list (vector) that's composed of functions such as 
> complex exponentials and Bessel functions.  Some of the functions are common 
> to each element of the list.  I'm trying to find a way to do the following:
> 
>    {a x, a y, a z}-> a *{x, y, z}
> 
> In this expression, a, x, y, z are polynomials, exponentials and/or Bessel 
> functions.
> 
> So far I haven't had any luck with this.  Does anyone have a simple 
> solution?
> 
> John Reed 
>