Re: proper way to manipulate lists?

*To*: mathgroup at smc.vnet.net*Subject*: [mg40196] Re: proper way to manipulate lists?*From*: bobhanlon at aol.com (Bob Hanlon)*Date*: Tue, 25 Mar 2003 14:49:00 -0500 (EST)*References*: <b5p158$7sk$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

n=3; data = Table[ToExpression[#<>ToString[k]& /@ {"x","y"}],{k,1,n}]; data2 = data /. {x_,y_}:>{a*x,b*y} {{a x1,b y1},{a x2,b y2},{a x3,b y3}} data3 = {a,b}*#& /@ data {{a x1,b y1},{a x2,b y2},{a x3,b y3}} Bob Hanlon In article <b5p158$7sk$1 at smc.vnet.net>, Nathan Moore <nmoore at physics.umn.edu> wrote: << Subject: proper way to manipulate lists? From: Nathan Moore <nmoore at physics.umn.edu> To: mathgroup at smc.vnet.net Date: Tue, 25 Mar 2003 07:40:24 +0000 (UTC) I'm sure this is a one-liner, but it has stumped me for years. Suppose I'm working with a 2-d array of data, data = {{x1,y1},{x2,y2}...{xN,yN}}; and I want to transform the data according to, data2 = {{x1*a,y1*b},{x2*a,y2*b}...{xN*a,yN*b}}; The only way I know to do this is to move the data to excel, performing the transform and then move the data back to Mathematica. This is crazy - there must be a better way - is there? Please tell me there is! >><BR><BR>