Re: Assigning a list to coefficients

*To*: mathgroup at smc.vnet.net*Subject*: [mg13925] Re: [mg13883] Assigning a list to coefficients*From*: Hugh Walker <hwalker at gvtc.com>*Date*: Mon, 7 Sep 1998 01:22:50 -0400*Sender*: owner-wri-mathgroup at wolfram.com

"Toshiyuki Meshii" <tm60 at cornell.edu> writes --------Begin message------ How can I assign a list to a coefficient with an index? That is, I have a list A which has data A={a1, a2, a3, ....., an} all the components of A is numerical value. And I want to assign the coefficients ci used in f[x_]=Sum[ ci * x ,{i=1,n}] at the later stage to the list A. How can I do it? I want to do some work such as differentiating f[x] symbolically, so I do not want to use A[[i]] in the Sum. -------End Message------- Toshiyuki, Here is an example of how to do what you want. coefList = Table[Random[],{k,0,10}] xList = Table[x^k,{k,0,10}] f = Apply[Plus,coefList xList] der1 = D[f,x] der2 = D[f,{x,2}] I arbitrarily have chosen the coefficients as a list of random numbers. I hope this example helps. Best wishes! Hugh Walker University of Houston Retired Gnarly Oaks