Struct CChart 

pub struct CChart { /* private fields */ }

Count of defects per unit (C) chart.

Monitors the total number of defects observed in a constant area of opportunity (inspection unit). Based on the Poisson distribution.

Formulas

• CL = c-bar (mean defect count)
• UCL = c-bar + 3 * sqrt(c-bar)
• LCL = max(0, c-bar - 3 * sqrt(c-bar))

Reference

Montgomery, D.C. (2019). Introduction to Statistical Quality Control, 8th ed., Chapter 7, Section 7.4.

Implementations

impl CChart

pub fn new() -> Self

Create a new C chart.

pub fn add_sample(&mut self, defects: u64)

Add a defect count for one inspection unit.

pub fn control_limits(&self) -> Option<(f64, f64, f64)>

Get the control limits as (ucl, cl, lcl), or None if no data.

pub fn points(&self) -> &[AttributeChartPoint]

Get all chart points.

pub fn is_in_control(&self) -> bool

Check if the process is in statistical control.

Trait Implementations

impl Default for CChart

fn default() -> Self

Returns the “default value” for a type.