RE: generalized foldlist problem

*To*: mathgroup at smc.vnet.net*Subject*: [mg69113] RE: [mg69057] generalized foldlist problem*From*: "David Park" <djmp at earthlink.net>*Date*: Wed, 30 Aug 2006 06:33:59 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

Arek, You will probably get better answers but here is one approach. list1 = {a, b, c, d, e}; list2 = {3, 2, 5, 1, 6}; f[i_] := Take[ Join[Array[0 &, i - 1], Array[Part[list1, i] &, Part[list2, i]], Array[0 &, 5]], 5] Fold[#1 + f[#2] &, {0, 0, 0, 0, 0}, Range[5]] {a, a + b, a + b + c, c + d, c + e} David Park djmp at earthlink.net http://home.earthlink.net/~djmp/ From: Arkadiusz Majka [mailto:Arkadiusz.Majka at telekomunikacja.pl] To: mathgroup at smc.vnet.net DearAll, Please, help! I have two list list1={a,b,c,d,e} list2={3,2,5,1,6} and I want to apply a modified version of FoldList to list1 in the following way: list2 indicates that element a appears only 3 times (if space enough) beginning from the beginning of the list , element b appears 2 times, c - 5 times , etc. So the output should be GeneralizedFoldList[list1,list2]={a,a+b,a+b+c,c+d,c+e} Thanks for any hints, arek