RE: Suggestions for translating a Do[] loop ...
- To: mathgroup at smc.vnet.net
- Subject: [mg69796] RE: [mg69773] Suggestions for translating a Do[] loop ...
- From: "Erickson Paul-CPTP18" <Paul.Erickson at Motorola.com>
- Date: Sat, 23 Sep 2006 04:44:53 -0400 (EDT)
It would seem (Drop[ a * b, -1] + Drop[ r, 1]) / (1 + Drop[ b, -1] * Drop[ r, 1]) Should work Paul -----Original Message----- From: David Annetts [mailto:davidannetts at aapt.net.au] To: mathgroup at smc.vnet.net Subject: [mg69796] [mg69773] Suggestions for translating a Do[] loop ... Hi, Given that a, b & r are lists of the same length, can anyone suggest a translation of the following Do[] loop to something functional? It looks like an ideal application for Fold, but for me, the loop going backwards is really obscuring things. The loop is Do[ r[[j]] = a[[j]] * (b[[j]] + r[[j + 1]]) / (1 + b[[j]] * r[[j + 1]]), {j, Length@a - 1, 1, -1} ]; with r[[Length@a]] = 0. Many thanks, Dave.