R help - Sep 2010 - performing script on multiple files

say that I have a script that uses read.csv to read a textfile in a 
certain directory, then transforming the data a bit and then spit out a 
new file in an output directory.
Is it possible to make this universal so the same procedure is made for 
all files in a certain directory and also make it spit out files that 
changes names for each file that is made (so the same output.csv is not 
overwritten every time the script runs)?

Jonas -
    Here's an (untested) idea:

readwrite = function(file,outputdirectory){
      dat = read.csv(file)
          . . .
      write.csv(dat,file =
paste(outputdirectory,sub('\\.csv','.new',file),sep='/'))
}

sapply(list.files('.',pattern='\\.csv$'),readwrite,'/some/location')

It will read all the .csv files in the current directory, and write out 
a file with the extension changed to .new in the directory /some/location .

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

On Fri, 24 Sep 2010, Jonas Josefsson wrote:
> say that I have a script that uses read.csv to read a textfile in a certain
> directory, then transforming the data a bit and then spit out a new file in
> an output directory.
> Is it possible to make this universal so the same procedure is made for all
> files in a certain directory and also make it spit out files that changes 
> names for each file that is made (so the same output.csv is not overwritten
> every time the script runs)?
>
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