What are options?

If you’ve never encountered the term “options” or the base R functions options(), getOption(), or, much less commonly, .Options() before, don’t worry! Simply put, options are a way to customize the behavior of a function or package, and are typically used to control the appearance of output or the behavior of a function. A fresh, bare installation of R has several dozen default options such as the number of significant figures to be displayed; this specific option can be viewed with getOption("digits"), and a list of all options currently set can be viewed with options().

# the default value for R installations should be 7
getOption("digits")
#> [1] 7

# this number will be printed to 7 *significant* digits
0.093573827689
#> [1] 0.09357383

Changing Options

You don’t typically need to adjust options yourself because the pre-chosen values are supposed to reflect sensible defaults. However, if you find that you’re frequently changing same setting over and over again, you might want to set an option to a different value. To change an option, you can use the options() function. Extending the previous note on significant figures, to change the number of digits displayed in significant notation, you can use options(digits = 3).

# change the number of significant digits to 3
options(digits = 3)

# this number will be printed to 3 *significant* digits
0.093573827689
#> [1] 0.0936

Automatically Set Options

These options are set automatically when the package is loaded. However, if you have set these options to different values, the package will respect your settings.

• ordinalsimr.default_iterations = 1000: The default number of iterations to run in the simulation.
• ordinalsimr.default_size_min = 30: The default minimum sample size for the simulation.
• ordinalsimr.default_size_max = 200: The default maximum sample size for the simulation.
• ordinalsimr.default_ratio = "50:50": The default ratio of the two groups in the simulation.

Non-Required Options

These options are not required to be set, but can be set to further customize the behavior of the Shiny application.

• ordinalsimr.default_entry_rows = NULL: The default number of rows to display in the data entry table. If set to NULL, the application has a fallback value of 3 rows.
• ordinalsimr.default_distributions = NULL: The default data set or distribution to use in the simulation. If set to NULL, the Shiny app will initialize with an empty data set. This option overrides any value set for ordinalsimr.default_entry_rows.

Setting and Getting {ordinalsimr} Options

To get or set options for the package, you can use the options() function as discussed in the first section of this vignette. For example, to set the default number of iterations to 500, you can use options(ordinalsimr.default_iterations = 500).

There are also two short-cut functions available for setting and getting options: set_ordinalsimr_options() and get_ordinalsimr_options(). These functions are wrappers around options() and are provided for convenience.

# get all package options
get_ordinalsimr_options()

# set the default number of iterations to 500
opt <- options()
set_ordinalsimr_options(
  default_iterations = 1000,
  default_size_min = 10,
  default_size_max = 175,
  default_ratio = "66:34",
  )

# get the current value of the default number of iterations
get_ordinalsimr_options()

# reset options
options(opt)

# display that the options have been reset
get_ordinalsimr_options()