UChart Class

public sealed class UChart : ControlChart<UChart>

Public NotInheritable Class UChart
	Inherits ControlChart(Of UChart)

public ref class UChart sealed : public ControlChart<UChart^>

[<SealedAttribute>]
type UChart = 
    class
        inherit ControlChart<UChart>
    end

Inheritance

Object  →  ControlChart  →  ControlChart<UChart>  →  UChart

The U chart is used when the number of defects per inspection unit is being monitored and the unit sizes may vary. When unit sizes vary, each observation has its own control limits; when the unit size is constant, the limits are identical across all observations.

Use the Series property to access the result series. It returns a PointwiseLimitSeries when variable unit sizes produce per-point limits, or a FixedLimitSeries when a constant unit size was used.

Typical usage (variable sizes):

double[] counts = { 4, 2, 6, 3, 5 };
double[] sizes  = { 5, 4, 6, 5, 4 };

// Phase I — establish limits
UChart chart = new UChart(Vector.Create(counts), Vector.Create(sizes));
chart.Analyze();

// Deploy for production monitoring
UChart deployed = (UChart)chart.Deploy();

// Phase II — apply to new data with new unit sizes
double[] newCounts = { 3, 5, 2 };
double[] newSizes  = { 5, 5, 4 };
UChart applied = deployed.Apply(
    Vector.Create(newCounts), Vector.Create(newSizes));

Reference