`qcc.options.Rd`

This function can be used to control the behavior of the 'qcc' library such as the background color, out-of-control points appearance, and many others.

`qcc.options(...)`

- ...
the option to be set or retrieved. See details.

The available options are:

`exp.R.unscaled`

a vector specifying, for each sample size, the expected value of the relative range (i.e. \(R/\sigma\)) for a normal distribution. This appears as \(d_2\) on most tables containing factors for the construction of control charts.

`se.R.unscaled`

a vector specifying, for each sample size, the standard error of the relative range (i.e. \(R/\sigma\)) for a normal distribution. This appears as \(d_3\) on most tables containing factors for the construction of control charts.

`beyond.limits$pch`

plotting character used to highlight points beyond control limits.

`beyond.limits$col`

color used to highlight points beyond control limits.

`violating.runs$pch`

plotting character used to highlight points violating runs.

`violating.runs$col`

color used to highlight points violating runs.

`run.length`

the maximum value of a run before to signal a point as out of control.

`bg.margin`

background color used to draw the margin of the charts.

`bg.figure`

background color used to draw the figure of the charts.

`cex`

character expansion used to draw plot annotations (labels, title, tickmarks, etc.).

`font.stats`

font used to draw text at the bottom of control charts.

`cex.stats`

character expansion used to draw text at the bottom of control charts.

If the functions is called with no argument return a list of available options.
If an option argument is provided the corresponding value is returned.
If a value is associated with an option argument, such option is set and the list of updated option values is invisibly returned.
In this case the list `.qcc.options`

is modified and any modification will remain in effect for the rest of the session.

```
old <- qcc.options() # save defaults
qcc.options("cex.stats") # get a single parameter
#> [1] 0.9
qcc.options("cex.stats"=1.2) # change parameters
qcc.options(bg.margin="azure2")
qcc.options("violating.runs" = list(pch = 15, col = "purple"))
qcc.options("beyond.limits" = list(pch = 15, col = "orangered"))
qcc(rnorm(100), type = "xbar.one", std.dev = 0.7) # see the results
#> ── Quality Control Chart ─────────────────────────
#>
#> Chart type = xbar.one
#> Data (phase I) = rnorm(100)
#> Number of groups = 100
#> Group sample size = 1
#> Center of group statistics = -0.09117297
#> Standard deviation = 0.7
#>
#> Control limits at nsigmas = 3
#> LCL UCL
#> -2.191173 2.008827
qcc.options(old) # restore old defaults
```