Re: Map function which adds last two numbers of a list

*To*: mathgroup at smc.vnet.net*Subject*: [mg73592] Re: Map function which adds last two numbers of a list*From*: "Dana DeLouis" <dana.del at gmail.com>*Date*: Thu, 22 Feb 2007 04:41:49 -0500 (EST)

Hi. Here's an option similar to Andrzej's excellent idea in case you have variables. z = {{1, 4, 5, 6}, {7, 8, c, d}, {1, 2, 4, 3}}; rule = ({w___, x_, y_})?VectorQ -> {w, x + y}; z /. rule {{1, 4, 11}, {7, 8, c + d}, {1, 2, 7}} HTH Dana -- Windows XP & Mathematica 5.2 "Christopher Pike" <crpike at ucdavis.edu> wrote in message news:ergqrb$jg0$1 at smc.vnet.net... > > Hi, > Consider this: > > z = {{1,4,5,6},{7,8,9,1},{1,2,4,3}} > > I'd like to Map a function onto z which would replace the last two items > with their sum: > > {{1,4,11},{7,8,10},{1,2,7}} > > I could easily use the Table command to construct this new table, but it > would be nicer if I new how to Map some function on z that would produce > the same result. > > Any suggestions. > > Thanks, Chris Pike >