Re: Re: Function of several variables

*To*: mathgroup at smc.vnet.net*Subject*: [mg72198] Re: [mg72132] Re: Function of several variables*From*: "Chris Chiasson" <chris at chiasson.name>*Date*: Thu, 14 Dec 2006 05:49:15 -0500 (EST)*References*: <eljaik$7dv$1@smc.vnet.net> <200612131139.GAA23652@smc.vnet.net>

What is the point of Sequence in the definition of f? On 12/13/06, Norbert Marxer <marxer at mec.li> wrote: > Hi Troy > > Try this > > f[p:Sequence[Subscript[_, _]...]] := Module[{}, 1/Total[{p}]] > > Then > > f[Subscript[x, 1], Subscript[x, 2], Subscript[x, 3]] > > will give you the inverted sum > > 1/(Subscript[x, 1] + Subscript[x, 2] + Subscript[x, 3]) > > Of course you can apply any functions (inside Module) to your > subscripted indices. > > Best Regards > Norbert Marxer > www.mec.li > > > tlhiv schrieb: > > > I have created a list of variables that I would like to make a function > > in terms of by > > > > M = 4; > > X = Table[Subscript[x, i], {i, 1, M}] > > > > Now I would like to make a function f that is a function of each of > > these M variables. If I were manually create this function without > > taking advantage of iterators, I would do something like > > > > f[Subscript[x,1]_,Subscript[x,2]_,Subscript[x,3]_,Subscript[x,4]_] = > > 1/(Subscript[x,1]+Subscript[x,2]+Subscript[x,3]+Subscript[x,4]) > > > > However, my plan is to significantly increase M, and therefore I don't > > want to have to manually define f in this way. I would like to define > > it in terms of the elements of X and use the Sum in the function > > definition. In the end I'm going to be solving an optimization problem > > where I try to find the "optimal" choice for these elements of X. Can > > someone offer a method for accomplishing this function definition? > > > > Thanks, > > > > -- > > Troy Henderson > > Assistant Professor > > Department of Mathematical Sciences > > United States Military Academy > > http://www.tlhiv.org > > -- http://chris.chiasson.name/

**References**:**Re: Function of several variables***From:*"Norbert Marxer" <marxer@mec.li>