Apply function to parts of a list

*To*: mathgroup at smc.vnet.net*Subject*: [mg86224] Apply function to parts of a list*From*: guerom00 <guerom00 at gmail.com>*Date*: Thu, 6 Mar 2008 02:59:51 -0500 (EST)

Hi all, Very often, I find myself having datas to plot of this form : data={{x1,y1},{x2,y2},{x3,y3}...{xn,yn}} So, very conventional : a list of abscissa and ordinate. Now, let's say I want to multiply by 2 all my ascissa. Right now, I write : MapAt[2*#&,data,Table[{i,1},{i,1,Length[data]}]] It's OK but I isn't there another way to achieve this as I find this rather "involved" for such a simple thing ? Thanks in advance.

**Follow-Ups**:**Re: Apply function to parts of a list***From:*Stern <nycstern@gmail.com>

**Re: Apply function to parts of a list***From:*Curtis Osterhoudt <cfo@lanl.gov>

**Re: Apply function to parts of a list***From:*"Thomas Dowling" <thomasgdowling@gmail.com>