How to reverse sign on the y's in a list of (x, y)'s?

*To*: mathgroup at smc.vnet.net*Subject*: [mg61231] How to reverse sign on the y's in a list of (x, y)'s?*From*: sherifffruitfly at gmail.com*Date*: Thu, 13 Oct 2005 01:39:38 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

Hi all, This is really dumb, but I just don't know how to do it... Import from excel gives me a list of ordered pairs, and I want the 2nd element of each pair to be of opposite sign. Sticking the negative sign in front of the entire Import statement reverses both the 1st and the 2nd elements (duh). How do I get just the second item to reverse sign? thanks!

**Follow-Ups**:**Re: How to reverse sign on the y's in a list of (x, y)'s?***From:*curtis <gardyloo@mail.wsu.edu>

**Re: How to reverse sign on the y's in a list of (x, y)'s?***From:*Murray Eisenberg <murray@math.umass.edu>

**Re: How to reverse sign on the y's in a list of (x, y)'s?***From:*János <janos.lobb@yale.edu>

**Re: How to reverse sign on the y's in a list of (x, y)'s?***From:*ggroup@sarj.ca

**Re: How to reverse sign on the y's in a list of (x, y)'s?***From:*<bsyehuda@gmail.com>

**Re: How to reverse sign on the y's in a list of (x, y)'s?***From:*Yasvir Tesiram <tesiramy@omrf.ouhsc.edu>