It's probably best if you start learning R by reading the introductory material and trying it out. If the going gets tough, persevere. Trying to learn R directly from R-help can get a bit tedious (on both sides).
Bill Venables
http://www.cmis.csiro.au/bill.venables/
-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of cruz
Sent: Thursday, 5 February 2009 1:36 PM
To: r-help at r-project.org
Subject: [R] non-numeric argument to binary operator
Hi,
I compute the value of xi*xj by "for" loops, this how I try: