Hi, You didn't provide any example data. So, I am not sure whether this helps.
set.seed(15) dat1<-data.frame(A=sample(10:20,5,replace=TRUE),B=sample(18:28,5,replace=TRUE),C=sample(25:35,5,replace=TRUE),D=sample(20:30,5,replace=TRUE)) dat2<-dat1[,-1] # I forgot to paste this line res<-lapply(lapply(seq_len(ncol(dat2)),function(i) t.test(dat2[,i],dat1[,1],paired=TRUE)),function(x) data.frame(meanDiff=x$estimate,p.value=x$p.value))# paired names(res)<-paste("A",LETTERS[2:4],sep="") res<- do.call(rbind,res) res # meanDiff p.value #AB 9.4 0.021389577 #AC 15.0 0.002570261 #AD 10.6 0.003971604 #or res1<-lapply(lapply(seq_len(ncol(dat2)),function(i) t.test(dat2[,i],dat1[,1],paired=FALSE)),function(x) data.frame(mean=x$estimate,p.value=x$p.value)) names(res1)<-paste("A",LETTERS[2:4],sep="") res1<-do.call(rbind,res1) row.names(res1)[grep("mean of y",row.names(res1))]<-gsub("(.*\\.).*","\\1A",row.names(res1)[grep("mean of y",row.names(res1))]) row.names(res1)[grep("mean of x",row.names(res1))]<-gsub("(\\w)(\\w)(\\.).*","\\1\\2\\3\\2",row.names(res1)[grep("mean of x",row.names(res1))]) res1 # mean p.value #AB.B 25.2 1.299192e-03 #AB.A 15.8 1.299192e-03 #AC.C 30.8 5.145519e-05 #AC.A 15.8 5.145519e-05 #AD.D 26.4 1.381339e-03 #AD.A 15.8 1.381339e-03 A.K. ----- Original Message ----- From: Yao He <yao.h.1...@gmail.com> To: r-help@r-project.org Cc: Sent: Sunday, January 6, 2013 10:20 PM Subject: [R] how to aggregate T-test result in an elegant way? Dear all: Plan 1: I want to do serval t-test means for different variables in a loop , so I want to add all results to an object then dump() them to an text. But I don't know how to append T-test result to the object? I have already plot the barplot and I want to know an elegant way to report raw result. Can anybody give me some pieces of advice? Yao He ————————————————————————— Master candidate in 2rd year Department of Animal genetics & breeding Room 436,College of Animial Science&Technology, China Agriculture University,Beijing,100193 E-mail: yao.h.1...@gmail.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.