From: "Älphä Blüë" Date: 2009-07-22T07:53:51+09:00 Subject: Re: Standard Deviation question regarding EDOM errors Hi David, I think I understand what you are saying.. What I want with.. product += a*a is .. a[0]*a[0]+a[1]*a[1]+a[2]*a[2]..etc. -- Posted via http://www.ruby-forum.com/.