Tidy the control limits of a Shewhart chart — tidy.shewhart

Returns a tibble of the chart's control limits in tall format. Each row corresponds to one line of one chart panel (CL / UCL / LCL).

Usage

# S3 method for class 'shewhart_chart'
tidy(x, ...)

Arguments

x: A shewhart_chart object.
...: Currently unused.

Value

A tibble with at least columns chart, line, value. For regression charts, whose limits follow a fitted curve, the tibble is in long format with one row per phase, endpoint and line: columns chart ("regression"), .phase, endpoint ("first" / "last" observation of the phase), line ("CL", "UCL", "LCL") and value.

Examples

fit <- shewhart_i_mr(data.frame(y = rnorm(50)), value = y)
broom::tidy(fit)
#> # A tibble: 6 × 3
#>   chart line   value
#>   <chr> <chr>  <dbl>
#> 1 I     CL    -0.255
#> 2 I     UCL    3.26 
#> 3 I     LCL   -3.77 
#> 4 MR    CL     1.32 
#> 5 MR    UCL    4.32 
#> 6 MR    LCL    0