Re: subscripted variables in Modules

*To*: mathgroup at smc.vnet.net*Subject*: [mg30116] Re: subscripted variables in Modules*From*: "Orestis Vantzos" <atelesforos at hotmail.com>*Date*: Sat, 28 Jul 2001 22:08:53 -0400 (EDT)*Organization*: National Technical University of Athens, Greece*References*: <9jtkij$89j$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

If you define X as a local variable and take care to use UpSet(^=) and UpSetDelayed(^:=) for any definitions involving Subscript[X,i] then everything works fine. Orestis "Arny" <someone at somewhere.sometime> wrote in message news:9jtkij$89j$1 at smc.vnet.net... > Hello All, > > (After some effort) I have gotten a proggy with subscripted variables to do > what I want and have come to appreciate the utility of Mathematica's > decision to not declare subscripted variables as variables but as > expressions, i.e. > > In: FullForm[X_i] > Out: SubScript[X,i] > > The value being that one can create formulas with subscripted variables, > then apply replacement rules that automatically handle the iterators, i.e.: > > In: Sum[X_i , {i,n} ] /. {n->Length[data], X_i -> data[[i]]} > Out:data[[1]] + data[[2]] + data[[3]] + ... etc ...+ data[[Length[data]]] > > Ok, no problem. However when I do my algorithm inside of a Module[] I am > not able to declare X_i as a local variable because it isn't a variable, it > is an expression. So long as I am not using X_i's elsewheres this is no > problem, but of course I would like to protect everything and would like to > do so. > > Any suggestions???? > > B > -- > Bernard Gress > Department of Economics > University of California, Riverside > 1150 University Ave. > Riverside, CA 92521-0247 > Fax: (909) 787-5685 > Phone: (909) 778 9813 > BGRESS at MAIL.UCR.EDU > http://csep.ucr.edu/staff/bernard/index.htm > > >