[R] Changing names of a string variable

Phil Spector spector at stat.berkeley.edu
Tue Dec 7 20:32:37 CET 2010


Jahan -
    Try

dat$target = toupper(dat$target)

I would not recommend a loop for something 
like this.

(You might also want to brush up on your python,
because what you're trying doesn't work in 
python either.)

 					- Phil Spector
 					 Statistical Computing Facility
 					 Department of Statistics
 					 UC Berkeley
 					 spector at stat.berkeley.edu




On Tue, 7 Dec 2010, Jahan wrote:

> Hello,
> Here is the data set I am working with:
> dat=read.csv('http://dl.dropbox.com/u/1852742/relexpressions.csv')
> names(dat)
>
> #Under the 'target' column, I want to change all of the values into
> all capital letters (e.g. fgf2 becomes FGF2).  I have taken a loop
> approach but I think my Python background is confusing me.  Here is
> what I attempted:
>
> for(line in dat[,1]){if(line=='fgf2'){line<-'FGF2'}}
> #I made sure that it was looping through each line by entering:
> for(line in dat[,1]){if(line=='fgf2'){print(line)}} #Which did exactly
> what I thought it would.
>
> #This doesn't change anything, though.  Also, after reading the
> documentation I am still confused how to add multiple "if"
> statements.  I would need that because I need to change the names of
> fgf2, fgf7, and fgf10.
>
> #I am sure there is a built-in function to do what I need, but I
> haven't found it yet so I tried this loop method.  Any help is greatly
> appreciated!
>
> Jahan
>
> ______________________________________________
> R-help at 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.
>



More information about the R-help mailing list