error reading and merging a folder of data into one dataframe - r

Question

If it helps, I'm running R 3.3.1 on a Macbook Pro OS El Captain...
I am trying to read in a folder of similar data files. I've checked the directory and the files are where they should be:
list.files('../data/')
[1] "B101.txt" "B101p2.txt" "B116.txt" "B6.txt" "B65.txt" "B67.txt" "B67p2.txt"
[8] "B70.txt" "B71.txt" "B71p2.txt" "B95.txt" "B95p2.txt" "B96.txt" "B96p2.txt"
[15] "B98.txt" "B98p2.txt" "B99.txt" "B99p2.txt"
The following is my code and error:
a = ldply(
.data = list.files(
path = '../data/'
)
, .fun = function(x){
to_return = read.table(
file = x
, skip = 20
, sep = '\t'
, fill = TRUE
)
return(to_return)
}
, .progress = 'text'
)
Error in file(file, "rt") : cannot open the connection
In addition: Warning message:
In file(file, "rt") :
cannot open file 'B101.txt': No such file or directory
I do not know what the problem is as all searches for those errors suggest fixing the directory. I have also checked the data files and can read an individual file using:
read.table('../data/B101.txt', skip = 20, sep = '\t', fill=TRUE)
Could someone please help me to fix the problem of reading in the whole folder. I'm trying to sort out the script with a small number of files but will need it to run for a much larger number, so reading them in one by one isn't practical. Thanks.

Answer 1

By default, list.files returns only the filename itself, not including the leading (relative or absolute) path (if any). When dealing with files potentially in another directory, you need to include full.names = TRUE:
a = ldply(
.data = list.files(
path = '../data/',
full.names = TRUE
)
, .fun = function(x){
to_return = read.table(
file = x
, skip = 20
, sep = '\t'
, fill = TRUE
)
return(to_return)
}
, .progress = 'text'
)