Set or return options for the qcc package.

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(...)

Arguments

...

the option to be set or retrieved. See details.

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.

Value

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.

Author

Luca Scrucca

See also

qcc

Examples

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