Example Code Guide
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User Manual:
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README
argparser is a cross-platform command-line argument parser for R, written in R, with no external
dependencies. This package is useful with the Rscript front-end and facilitates turning an R
script into an executable script.
History
v0.4 (in progress) Incompatibility: '-' in argument names are substitute by '_'
v0.3 Added support for multi-valued arguments
v0.2 Function names change Incompatibility: '.' in function names are replaced with '_'
v0.1 Initial release
Dependencies
R (>= 3.0)
roxygen2 (>= 4.0, for building only)
Build
Clone the repository, build the documentation with roxygen2, then install.
$ git clone https://bitbucket.org/dshih/argparser.git
$ cd argparser
$ R
R> library(roxygen2)
R> roxygenize()
R> quit()
$ R CMD INSTALL .
Usage
Create a R script (e.g. round.R) with a shebang line (Linux only).
Import the argparser library, create a parser, populate the parser with arguments and parse
the command line arguments.
#!/usr/bin/env Rscript
library(argparser, quietly=TRUE)
# Create a parser
p <- arg_parser("Round a floating point number")
# Add command line arguments
p <- add_argument(p, "number", help="number to round", type="numeric")
p <- add_argument(p, "--digits", help="number of decimal places", default=0)
# Parse the command line arguments
argv <- parse_args(p)
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# Do work based on the passed arguments
cat( round(argv$number, argv$digits), "\n")
Then, set the R script as executable and execute (Linux only).
$ chmod +x round.R
# Print the help message
$ ./round.R -h
Alternatively, run the script using Rscript (Linux or Windows).
$ Rscript round.R 3.141
# 3
$ Rscript round.R 3.141 -d 2
# 3.14
For R help, see ?argparser.
