performing function on data frame
Dear karin,
Try rescaler from the reshape package:
install.packages("reshape")
library("reshape")
newDF <- apply(oldDF, 2, rescaler, type = "sd")
HTH,
Thierry
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ir. Thierry Onkelinx
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-----Oorspronkelijk bericht-----
Van: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
Namens Karin Lagesen
Verzonden: donderdag 16 april 2009 12:29
Aan: r-help at r-project.org
Onderwerp: Re: [R] performing function on data frame
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 ______________________________________________ R-help at r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. Dit bericht en eventuele bijlagen geven enkel de visie van de schrijver weer en binden het INBO onder geen enkel beding, zolang dit bericht niet bevestigd is door een geldig ondertekend document. The views expressed in this message and any annex are purely those of the writer and may not be regarded as stating an official position of INBO, as long as the message is not confirmed by a duly signed document.