Description Usage Arguments Value Acknowledgement Author(s) References See Also Examples
parse_args
parses command line options using an
OptionParser
instance for guidance.
1 2 3 4 | parse_args(object,
args = commandArgs(trailingOnly = TRUE),
print_help_and_exit = TRUE,
positional_arguments = FALSE)
|
object |
An |
args |
A character vector containing command line
options to be parsed. Default is everything after the
Rscript program in the command line. If
|
print_help_and_exit |
Whether |
positional_arguments |
Whether |
Returns a list containing option values if
positional_arguments
is FALSE
(the
default). Otherwise returns a list with field
options
containing our option values as well as
another field args
which contains a vector of
positional arguments.
A big thanks to Steve Lianoglou for a bug report and patch; Juan Carlos Borrás for a bug report; Jim Nikelski for a bug report and patch; Ino de Brujin and Benjamin Tyner for a bug report; Jonas Zimmermann for bug report; Miroslav Posta for bug reports.
Trevor Davis.
Python's optparse
library, which inspired this
package, is described here:
http://docs.python.org/library/optparse.html
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 | # example from vignette
option_list <- list(
make_option(c("-v", "--verbose"), action="store_true", default=TRUE,
help="Print extra output [default]"),
make_option(c("-q", "--quietly"), action="store_false",
dest="verbose", help="Print little output"),
make_option(c("-c", "--count"), type="integer", default=5,
help="Number of random normals to generate [default %default]",
metavar="number"),
make_option("--generator", default="rnorm",
help = "Function to generate random deviates [default \"%default\"]"),
make_option("--mean", default=0,
help="Mean if generator == \"rnorm\" [default %default]"),
make_option("--sd", default=1, metavar="standard deviation",
help="Standard deviation if generator == \"rnorm\" [default %default]")
)
parse_args(OptionParser(option_list = option_list), args = c("--sd=3", "--quietly"))
# example from vignette using positional arguments
option_list2 <- list(
make_option(c("-n", "--add_numbers"), action="store_true", default=FALSE,
help="Print line number at the beginning of each line [default]")
)
parser <- OptionParser(usage = "%prog [options] file", option_list=option_list2)
parse_args(parser, args = c("--add_numbers", "example.txt"), positional_arguments = TRUE)
parse_args(parser, args = c("-add_numbers", "example.txt"), positional_arguments = TRUE)
|
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