spcConstants

fun spcConstants(subgroupSize: Int): SpcConstants(source)

Returns the standard SPC constants for the given subgroupSize.

The constants are tabulated for subgroup sizes 2 through 25, covering the range used in practice for Shewhart control charts. They are sourced from Montgomery's "Introduction to Statistical Quality Control" (7th ed.), Appendix VI.

Example:

val c = spcConstants(4)
c.a2 // 0.729
c.d4 // 2.282
c.b4 // 2.266

Return

the SpcConstants for that subgroup size.

Parameters

subgroupSize

the number of observations in each subgroup (must be in 2..25).

See also