[R] Using the system command
B.Rowlingson at lancaster.ac.uk
Fri Sep 12 13:48:45 CEST 2003
Suzy Smith wrote:
> Hello, I am currently taking a statistics course and we are to do a project producing a graph using multiple input files.
> In R, I'm trying to build a filelist based on a pattern. For some reason, if I do the command interactively and not assign it to an array variable I get what I thought I should, but if I do this inside my R program it chops off some file names and thinks there are two.
> I looked on the R website and found that there is an 8,096 character limit when using a character array but mine chops at 119.
> Here is the command:
> filelist <- system(paste("ls ", INPUTFILES, sep=""),intern=T)
> Any help would be much appreciated.
I dont know why that doesn't work - it might be specific to the files
on your system. However, R has some functions for finding files, such as
> filelist <- list.files(pattern=".dat$")
 "jobacct.dat" "winmail.dat"
Get more info by typing ?list.files
The following functions may also be useful:
file.access(base) Ascertain File Accessibility
file.choose(base) Choose a File Interactively
file.info(base) Extract File Information
file.path(base) Construct Path to File
file.show(base) Display One or More Files
More information about the R-help