Hi r-help-boun...@r-project.org napsal dne 03.05.2010 16:24:11:
> > I am conducting a very simple t test for two genes using lapply (i try to > avoid loop since i will have thousands of genes later on). however, I got > strange error msg like the followings. It looks that R is complaining my > factor has only one level, which is not the case (I check many times). In each split? sum(rowSums(sapply(split(all$treatment,all$CHIPEXP_NAME), function(x) table(x))>0)<2) shall tell you if there are some parts of your split which has only 1 or less non empty levels. What is the result in your case? Shall be zero. Regards Petr > > > result<- lapply(split(all,all$CHIPEXP_NAME),function(x) > > lm(logvalue~treatment,x)) > Error in `contrasts<-`(`*tmp*`, value = "contr.treatment") : > contrasts can be applied only to factors with 2 or more levels > > > can anyone help me to dissect this problem? > > thanks in advance. > > > -- > View this message in context: http://r.789695.n4.nabble.com/strange-error-msg- > from-lapply-and-lm-tp2124042p2124042.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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. ______________________________________________ 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.