MathGroup Archive 2002

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

Search the Archive

Re: finding independent variable groups

Assuming that you do not want the expression to evaluate before determining
or acting at the positions, here are two suggestions (I have added an extra

    Rest/@Position[Hold[(x/y) Exp[z x/y]],x/y]


    Hold[(x/y) Exp[z x/y]]/.x/y->u


Now remove Hold




Allan Hayes
Mathematica Training and Consulting
Leicester UK
hay at
Voice: +44 (0)116 271 4198
Fax: +44 (0)870 164 0565

"Ioan Alexandre Romoscanu" <romoscanu at> wrote in message
news:a2b3mv$lhd$1 at
> I wonder if it is possible to do the following formula manipulation
> task with Mathematica.
> Suppose you have a function of 3 variables [x,y,z], where only the
> ratio x/y occurs. Example
> f[x_,y_,z_]=(x/y) Exp[z]
> If now you have a large formula of more than 3 variables, where
> however certain variables always occur grouped together, in the same
> pattern (like x and y above).
> Is there a way to make Mathematica find out such groups of variables
> in a larger expression?
> Thank you for any help
> A.I.R.

  • Prev by Date: Re: Thread? Through? Operate?
  • Next by Date: Re: distance Frame <-> labels?
  • Previous by thread: finding independent variable groups
  • Next by thread: RE: finding independent variable groups