Using R to download gzipped data file, extract, and import data

Question

A follow up to this question: How can I download and uncompress a gzipped file using R? For example (from the UCI Machine Learning Repository), I have a file of insurance data. How can I download it using R?

Here is the data url: http://archive.ics.uci.edu/ml/databases/tic/tic.tar.gz.

Answer 1

I like Ramnath's approach, but I would use temp files like so:

tmpdir <- tempdir()

url <- 'http://archive.ics.uci.edu/ml/databases/tic/tic.tar.gz'
file <- basename(url)
download.file(url, file)

untar(file, compressed = 'gzip', exdir = tmpdir )
list.files(tmpdir)

The list.files() should produce something like this:

[1] "TicDataDescr.txt" "dictionary.txt"   "ticdata2000.txt"  "ticeval2000.txt"  "tictgts2000.txt" 

which you could parse if you needed to automate this process for a lot of files.

Answer 2

Here is a quick way to do it.

# create download directory and set it
.exdir = '~/Desktop/tmp'
dir.create(.exdir)
.file = file.path(.exdir, 'tic.tar.gz')

# download file
url = 'http://archive.ics.uci.edu/ml/databases/tic/tic.tar.gz'
download.file(url, .file)

# untar it
untar(.file, compressed = 'gzip', exdir = path.expand(.exdir))

Answer 3

Please the content of help(download.file) for that. If the file in question is merely a gzipped but otherwise readable file, you can feed the complete URL to read.table() et al too.