Thank you for your help.... Yes i wanted to do the t test for all columns except for the grouping column.....
2011/9/12 Uwe Ligges <lig...@statistik.tu-dortmund.de> > > > On 12.09.2011 13:16, Raphael Saldanha wrote: > >> Hi! >> >> Try something like this: >> >> subset(example, disease==TRUE) >> subset(example, disease==FALSE) >> > > > Hmmm, I think the actual answer to the question is something along this > line: > > sapply(example[names(example)!**="disease"], > function(x) t.test(x ~ example[["disease"]])[[3]]) > > > Uwe Ligges > > > > > >> On Mon, Sep 12, 2011 at 4:54 AM, C.H.<chainsawti...@gmail.com> wrote: >> >> Dear R experts, >>> >>> Suppose I have an data frame likes this: >>> >>> example<- data.frame(age=c(1,2,3, 4,5,6), >>>> >>> height=c(100,110,120,130,140,**150), disease=c(TRUE, TRUE, TRUE, FALSE, >>> FALSE, >>> FALSE)) >>> >>> example >>>> >>> age height disease >>> 1 1 100 TRUE >>> 2 2 110 TRUE >>> 3 3 120 TRUE >>> 4 4 130 FALSE >>> 5 5 140 FALSE >>> 6 6 150 FALSE >>> >>> Is there anyway to compare the age and height between those with >>> disease=TRUE and disease=FALSE using t.test and extract the p-values >>> quickly? >>> >>> I can do this individually >>> >>> t.test(example$age~example$**disease)[3] >>> >>> But when the number of variable grow to something like 200 it is not >>> easy any more. >>> >>> Thanks! >>> >>> Regards, >>> >>> CH >>> >>> -- >>> CH Chan >>> >>> ______________________________**________________ >>> R-help@r-project.org mailing list >>> https://stat.ethz.ch/mailman/**listinfo/r-help<https://stat.ethz.ch/mailman/listinfo/r-help> >>> PLEASE do read the posting guide >>> http://www.R-project.org/**posting-guide.html<http://www.R-project.org/posting-guide.html> >>> and provide commented, minimal, self-contained, reproducible code. >>> >>> >> >> >> > ______________________________**________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/**listinfo/r-help<https://stat.ethz.ch/mailman/listinfo/r-help> > PLEASE do read the posting guide http://www.R-project.org/** > posting-guide.html <http://www.R-project.org/posting-guide.html> > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ R-help@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.