File not found using fread

Question

I've got some basic code for reading in multiple files from a folder that share the same file format. The text files themselves each contain one or two sentences; no columns, headers or anything like that.

I initally used read.table to do this but after doing some reading round and in particular looking at this recent post I thought I'd see if I could use fread to make things a little bit quicker.

library(data.table)

files <- list.files(path = "C:/Documents", pattern = "*.txt")

readdata <- function(x)
{
    mydata <- fread(x, sep=" ")
    return(mydata)
}

all.files <- lapply(files, readdata)
final.data <- rbindlist(all.files)

When I run this code, I get the following error:

Error in fread(x, sep = " ") : File not found: 1.txt

1.txt is the first file in the folder. Can anyone figure out why this? The path folder is correct (I changed the one above to something generic to put on here) so I can't seem to see what the problem is.

yep. I've just tried getwd() now and it indicates what you've written. — user1988898

Sven Hohenstein Sven Hohenstein · Accepted Answer · 2014-01-16T12:25:41

You have to specify the path to the file:

path <- "C:/Documents"

readdata <- function(x)
{
  f <- file.path(path, x)
  mydata <- fread(f, sep=" ")
  return(mydata)
}

Another option is to use list.files with the argument full.names = TRUE. This returns the filenames together with their path.

files <- list.files(path = "C:/Documents", pattern = "*.txt", full.names = TRUE)

readdata <- function(x)
{
    mydata <- fread(x, sep=" ")
    return(mydata)
}

File not found using fread

1 Answers