Message-ID: <ypx6bpqwzycd.fsf@alanine.uio.no>
Date: 2009-04-16T10:28:50Z
From: Karin Lagesen
Subject: performing function on data frame
In-Reply-To: <979ffa270904150738l51077907p4ecbc8a61d64a142@mail.gmail.com> (David Hajage's message of "Wed\, 15 Apr 2009 16\:38\:45 +0200")
David Hajage <dhajage.r at gmail.com> writes:
> Hi Karin,
>
> I'm not sure I understand... Is this what you want ?
>
> d$y - mean(d$y)/sd(d$y)
Yes, and also a bit no.
Each column in my data frame represents one data set. For every
element in this data set I want to know the z value for that
element. I.e: I want to create a new data frame from the old data
frame, where each element in the new data frame is
newDF[i,j] = oldDF[i,j] - mean(d[,j]) / sddev(d[,j])
I could, I think, iterate like this over the data frame, but I keep
thinking that one of the apply functions should be employed...
Karin
--
Karin Lagesen, Ph.D.
karin.lagesen at medisin.uio.no
http://folk.uio.no/karinlag