parse.args: Function to collect arguments when running R from the command...

In reader: Suite of Functions to Flexibly Read Data from Files

Description

Allows parameter specification by A=..., B=... in the command line e.g, R < myScript.R M=1 NAME=John X=10.5, using commandArgs()

Usage

parse.args(arg.list = NULL, coms = c("X"), def = 0, list.out = F,
  verbose = TRUE)

Arguments

arg.list	the result of a commandArgs() call, or else NULL to initiate this call within the function
coms	list of valid commands to look for, not case sensitive
def	list of default values for each parameter (in same order)
list.out	logical, whether to return output as a list or data.frame
verbose	logical, whether to print to the console which assignments are made and warning messages

Value

returns dataframe showing the resulting values [column 1, "value"] for each 'coms' (rownames); or, if list.out=TRUE, then returns a list with names corresponding to 'coms' and values equivalent to 'value' column of the data.frame that would be returned if list.out=FALSE

Author(s)

Nicholas Cooper [e-mail]

Examples

parse.args(c("M=1","NAME=John","X=10.5"),coms=c("M","X","NAME"))
parse.args(c("N=1")) # invalid command entered, ignored with warning
temp.fn <- "tempScript1234.R"
# make a temporary R Script file to call using the command line
# not run # writeLines(c("require(reader)","parse.args(coms=c('M','X','NAME'))"),con=temp.fn)
bash.cmd <- "R --no-save < tempScript1234.R M=1 NAME=John X=10.5"
# run above command in the terminal, or using 'system' below:
# not run # arg <- system(bash.cmd)
# not run # unlink(temp.fn) # delete temporary file

reader documentation built on May 2, 2019, 9:27 a.m.