Skip to content

What is the R equivalent of STATA's 'drop' command?

4 messages · jjh21, stephen sefick, Kingsford Jones +1 more

#
Hello,

I am trying to do some data cleaning in R. I need to drop observations that
take on certain values of a variable. In STATA I might type something like:

drop if <variable name> == 3
drop if <variable name> == 4

Is there an R equivalent of this? I have tried playing around with the
subset command, but it seems a bit clunky. What would an advanced R user's
approach be for something like this?

Thank you!
#
It depends on how the data is set up (I am not an expert), but I have
had good results with the subset function.  subset(x, var!=3 & var!=4)
 this will take the subset of the dataframe x where var is not equal
to 3 or 4.

a <- rnorm(25)
var <- rep(c(1:5), 5)
x <- data.frame(a, var)
subset(x, var!=3 & var!=4)

Is this what you want?

Stephen Sefick
On Mon, Feb 9, 2009 at 7:27 PM, jjh21 <jjharden at gmail.com> wrote:

  
    
#
See ?"[" and its examples

Also, section 2.7 of An Introduction to R is a good place to start:

http://cran.r-project.org/doc/manuals/R-intro.html#Index-vectors

hth,
Kingsford Jones
On Mon, Feb 9, 2009 at 5:27 PM, jjh21 <jjharden at gmail.com> wrote:
#
Try something like

 rm(list=ls(pattern="y+"))

John

2009/2/10 stephen sefick <ssefick at gmail.com>: