procedure QCXChart(const Data: TMtx; const DrawVec: TVec; out CL: Double; out UCL: Double; out LCL: Double; Confidence: Double);
X-Chart ("XBar Chart").
| # | Name | Description |
|---|---|---|
| 1 | Data | Each Data row contains replicated observation taken at specific time. |
| 2 | Confidence | Confidence level for upper and lower control limit. Confidence must lie in the (0,1) interval. |
| 3 | DrawVec | Returns values to be drawn. |
| 4 | CL | Returns control Chart centerline. |
| 5 | UCL | Returns control Chart upper control limit. |
| 6 | LCL | Returns control Chart lower control limit. |
Result: stored in self (calling object)
Remarks:
This routine calculates X-Chart ("XBar Chart") drawing values, center line, upper and lower control limit.
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.
Examples
Uses StatSeries,StatControlCharts, MtxExp, Math387, MtxVecTee;
procedure Example;
var CL, UCL, LCL : double;
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;See Also: !:TQCSeries, QCSeries, StatControlCharts.QCSChart, StatControlCharts.QCRChart