StatControlCharts.QCCumSumChart Function

CUMSum chart.

Pascal

procedure QCCumSumChart(const Data: TMtx; const DrawVec: TVec; k: double; h: double; mean: double; sigma: double = 1.0; const SHigh: TVec = nil; const SLow: TVec = nil; Confidence: double = 0.997);

File

StatControlCharts

Parameters

Parameters	Description
Data	Each Data row contains replicated observation taken at specific time.
DrawVec	Returns values to be drawn.
k	Design parameter of the V-mask. k is the rise in the V-arm corresponding to one sampling unit.
h	Design parameter of the V-mask. h defines the rise in the arm coresponding to the distance from the origin to point vertex.
mean	Defines the estimate of the in-control mean.
sigma	Defines known (or estimated) standard deviation of the sample means.
SHigh	If set, returns high values for cumsum plot. When SHigh exceeds value h, the process is said to be out-of-control. Compare SHigh values to h to find if a process is out-of-control.
SLow	If set, returns low values for cumsum plot. When SLow exceeds value h, the process is said to be out-of-control. Compare SLow values to h to find if a process is out-of-control.
Confidence	Confidence level for upper and lower control limit. Confidence must lie in the (0,1) interval.

Description

Calculates CumSum Chart drawing values and additonal values, needed for deciding if some samples are out-of-control. See www.itl.nist.gov/div898/handbook/pmc/section3/pmc323.htmto learn more about Cumsum QC charts.

Example

Perform CumSum QC to determine if process is out-of-control.

var h,k,m,s: double;
  data: Matrix;
  sh,sl, s: Vector;
  outofcontrol: VectorInt;
begin
  data.LoadFromFile('process_data.mtx');
  // estimate k=0.32, h = 4.7
  k := 0.32;
  h := 4.7;
  // estimate process mean and sigma
  m := 230.3;
  s := 5.2;
  QCCumSumChart(data,s,k,h,m,s,sh,sl);
  // find point indexes which exceed h (out-of-control points)
  outofcontrol.FindIndexes(sh,'>',h);
end;

#include "MtxExpr.hpp"
#include "MtxExprInt.hpp"
#include "StatControlCharts.hpp"
void __fastcall Example();
{
  sMatrix data;
  data.LoadFromFile("process_data.mtx");

  sVector sh,sl,s;
  iVectorInt outofcontrol;

  // estimate k=0.32, h = 4.7
  double k = 0.32;
  double h = 4.7;
  // estimate process mean and sigma
  double m = 230.3;
  double sig = 5.2;
  QCCumSumChart(data,s,k,h,m,sig,sh,sl,0.997);
  // find point indexes which exceed h (out-of-control points)
  outofcontrol.FindIndexes(sh,">",h);
}

StatControlCharts, Functions, Example

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