Re: Re: Help please: Summing a list

*To*: mathgroup at smc.vnet.net*Subject*: [mg13588] Re: [mg13555] Re: [mg13480] Help please: Summing a list*From*: Jon Prudhomme <prudhomj at elwha.evergreen.edu>*Date*: Mon, 3 Aug 1998 03:53:50 -0400*Sender*: owner-wri-mathgroup at wolfram.com

Oops sorry, I should have said this: PP=Table[Apply[Plus,Take[P,n]],{n,1,Length[P]}] (That'll teach me to try it before I post it...) On Sat, 1 Aug 1998, Jon Prudhomme wrote: > > Rob, I think it would be easier to try this - > > PP=Table[Apply[Plus,Take[P,n]],{n,1,i}] > > Jon Prudhomme > The Evergreen State College > > On Sat, 1 Aug 1998, Keith S. Mersman wrote: > > > Rob, > > > > I think you want to do something like this: > > > > First, set up your original table: > > > > tab=Table[x,{x,0,110}] > > > > Then, assign a name to each of these entries like: > > > > Clear[P]; > > Table[P[i]=tab[[i]],{i,1,111}] > > > > This, this let P[i] be the i-1 entry in the table (labeled tab) > > > > Now, sum these values and label the totals: > > > > Table[PP[i]=Sum[P[n],{n,1,i}],{i,1,111}] > > > > This makes PP[i] be the sum of the first i entries of the orinal table. > > > > Now, creata a new table with these values: > > > > newtab=Table[PP[i],{i,1,111}] > > > > Hence, newtab is now a list with the ith value as the sum as the sum of > > the first i entries of tab. Let me know if this is what you wanted. > > > > > > On Sun, 26 Jul 1998 robpetersonSPAMME at iname.com wrote: > > > > > I make a list of numbers, eg: > > > > > > P=Table[6,{x,0,110}]; (I have a more interesting list to use later if I > > > get this working) > > > > > > Now I want to make another list PP in which each entry PP[[i]] is the > > > sum of P's first i entries. I try > > > > > > PP[[i]]:=Sum[P[[n]],{n,0,i}]; > > > > > > At the definition, I get the following error: Part::"pspec": > > > "Part specification \!\(n\) is neither an integer nor a list of > > > integers." > > > > > > I don't know how to make n an integer. In the definition of Sum[], it > > > seems n is an integer unless you add a forth parameter "di" in the > > > specification list such as > > > Sum[f, {i, imin, imax, di}] > > > > > > Can anyone help me to generate this second list? > > > > > > Thanks, Rob > > > > > > > > > > > > >