[R] colClasses

[Peter Dalgaard]

"Kalaylioglu, Zeynep (IMS)" <KalayliogluZ at imsweb.com> writes:

> Hi
> I am trying to read a data frame from a text editor in to R. I want some
> of the columns to be read in as "character" not numeric.
> I figured that I can do that by using "colClasses" in  "read.table"
> command. However, I couldn't find out how to use 
> "colClasses". e.g. say I have 5 column in the data file. I want 1st and
> 3rd column to be read in as character. How can I define
> this using colClasses?  (or is there a better way to do what I want?)

The easiest is probably

  read.table(....as.is=c(1,3)....)

but you could also do 

  cC <- rep(NA,5)
  cC[c(1,3)] <- "character"
  read.table(....colClasses=cC...)

which would be more readily generalized to "stranger" data types.

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark      Ph: (+45) 35327918
~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)             FAX: (+45) 35327907