QCXChart Routine

Summary

Constructs X-Chart ("XBar Chart").

Declaration

Procedure QCXChart(Data: TMtx; DrawVec: TVec; out CL, UCL, LCL: TSample; Confidence: TSample = 0.997);

Parameter	Description
Data	Each Data row contains replicated observation taken at specific time.
Confidence	Confidence level for upper and lower control limit. Confidence must lie in the (0,1) interval.
DrawVec	Returns values to be drawn.
CL	Returns control Chart centerline.
UCL	Returns control Chart upper control limit.
LCL	Returns control Chart lower control limit.

Description

When dealing with a quality characteristic that can be expressed as a measurement, it is customary to monitor both the mean value of the quality characteristic and its variability. Control over the average quality is exercised by the control chart for averages, usually called the XBar chart. For this chart type, the center line is defined by process grand mean and upper and lower control limits are defined by process standard deviation. Similarly, for R and S charts the center line is defined by process range and variability (standard deviation) respectively.

This routine calculates X-Chart ("XBar Chart") drawing values, center line, upper and lower control limit.

See Also
TQCSeries
QCSChart
QCRChart

Example 1

The following code loads data, stored in binary file and then creates a XBar chart.

  Uses StatSeries,StatControlCharts, MtxExp, Math387, MtxVecTee;
  procedure Example;
  var CL, UCL, LCL : TSample;
    Data: Matrix;
    DrawVec: Vector;
  begin
    Data.LoadFromFile('ewma_data.mtx');
    QCXChart(Data,DrawVec,CL,UCL,LCL,0.025);
    // DrawVec now stores values to-be-drawn
    // CL, LCL and UCL store XBar chart center,
    // lower and upper control limits respectively.
  end;

  #include "MtxVecCpp.h"
  #include "StatControlCharts.hpp"
  #include "Math387.hpp"
  void __fastcall Example();
  {
    Matrix Data;
    Vector DrawVec;
    double cl,ucl,lcl;
    Data->LoadFromFile("ewma_data.mtx");
    QCXChart(Data,DrawVec,cl,ucl,lcl,0.025);
  }

  using Dew.Math;
  using Dew.Math.Units;
  using Dew.Stats.Units;
  namespace Dew.Examples
  {
    private void Example()
    {
      Matrix Data;
      Vector DrawVec;
      double cl,ucl,lcl;
      Data.LoadFromFile("ewma_data.mtx");
      StatControlCharts.QCXChart(Data,DrawVec,out cl, out ucl, out lcl, 0.025);
    }
  }