Services & ResourcesWolfram ForumsMathGroup Archive

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

Re: listing user defined, independent variables

• To: mathgroup at smc.vnet.net
• Subject: [mg96782] Re: listing user defined, independent variables
• From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
• Date: Wed, 25 Feb 2009 04:00:39 -0500 (EST)
• Organization: Uni Leipzig
• References: <go0j0p$mta$1@smc.vnet.net>
• Reply-to: kuska at informatik.uni-leipzig.de

Hi,

a) what mean
    "Mathematica must 'know' which variables
     are functions of other symbols".
     Variables functions of other symbols ?? what should that be ??
b) Start a fresh kernel and type

blub[x_] := Module[{y, z}, x]

and

Names["Global`*"] gives

{"blub", "x", "x$", "y", "y$", "z", "z$"}

The "*$" symbols come from the Module[] and have th attribute Temporary
and the "blub" function has an DownValue[]. Since x,y,z appear in the 
down values of blub[] it is not possible to find out if there is also a
global symbol with a that has the name "x", "y" or "z".

Regards
   Jens

Paul Ellsmore wrote:
> Hi,
> 
>  
> 
> I have a notebook in which there are over 1300 variables (symbols) defined.
> The vast majority of these are dependent variables. I can get a list of them
> all with Names["Global`*"], but what I really want is a list of only the
> independent variables. Is there any obvious way to do this? Mathematica must
> "know" which variables are functions of other symbols, so I was hoping that
> there would be an "attribute" of a dependent variable that I could use as a
> filter on Names[]. Any thoughts? I am using V5.1.
> 
>  
> 
> Cheers,
> 
>  
> 
> Paul
> 
>  
> 
> Dr. Paul A. Ellsmore
> 
>  
> 
> Nanion Limited
> 
> Oxford Centre for Innovation
> 
> Mill Street
> 
> Oxford
> 
> United Kingdom
> 
> OX2 0JX
> 
>  
> 
> Tel: +44 (0) 1865 811175
> 
> Fax: +44 (0) 1865 248594
> 
>  

• Follow-Ups:
  • Re: Re: listing user defined, independent variables
    • From: "Paul Ellsmore" <paul.ellsmore@nanion.co.uk>