Thanks Charles, when I use cbind.data.frame(), the column was not replaced by number. I could not find information about cbind.data.frame. what is the machineism of cbind.data.frame? cheers Yu
--- On Mon, 8/25/08, Charles Plessy <[EMAIL PROTECTED]> wrote: From: Charles Plessy <[EMAIL PROTECTED]> Subject: Re: [R] cbind in data.frame To: r-help@r-project.org Date: Monday, August 25, 2008, 6:09 AM Le Sun, Aug 24, 2008 at 10:56:43PM -0700, Yuan Jian a écrit : > hi, > when I used cbind to combine columns, some contents of columns has been replaced by > number. in the script below, column should be aaa,bbb,ccc but I was given 1,2,3. > but when I change the column to vector, it gave me correct contents. can you please > tell me why? > ? > > d<-read.table("aaa.txt") Hello, read.table converts characters to factors. Factors will be converted to numbers by cbind, as in the following example: > toto <- c("aaa","bbb","aaa") > toto [1] "aaa" "bbb" "aaa" > as.factor(toto) [1] aaa bbb aaa Levels: aaa bbb > cbind(as.factor(toto)) [,1] [1,] 1 [2,] 2 [3,] 1 The 'as.is' or 'colClasses' option of read.table will help you to prevent the conversion of characters to factors. Have a nice day, -- Charles Plessy http://charles.plessy.org Tsurumi, Kanagawa, Japan ______________________________________________ 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. [[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.