Example 009: Graph showing use of BestFitCoeffs

1// This example builds upon the basic CreateSimpleGraph '000' example chart //
2CreateSimpleGraph(Pego1);
3 
4// Reduce to just two subsets //
5Pego1.PeData.Subsets = 2;
6 
7// Set BestFitDegree and Plotting Method //
8Pego1.PePlot.Option.BestFitDegree = BestFitDegree.Third;
9Pego1.PePlot.Method = GraphPlottingMethod.PointsPlusBestFitCurve;
10 
11// Call PEreinitialize and PEresetimage //
12Pego1.PeFunction.Reinitialize();     // Reinitialize can be used to read ManualMaxY, etc
13Pego1.PeFunction.ResetImage(0, 0);   // ResetImage is needed to calculate coeffs.
14 
15// Now add annotations that represents coefficients //
16 
17//** First subset's coeffs. **'
18String t;
19t = "Texas y = " + String.Format( "{0:#.##}", Pego1.PePlot.Option.BestFitCoeffs[0, 3]) + "x^3 ";
20if(Pego1.PePlot.Option.BestFitCoeffs[0, 2] >= 0)
21    t = t + "+ ";
22t = t + String.Format("{0:#.##}", Pego1.PePlot.Option.BestFitCoeffs[0, 2]) + "x^2 ";
23if(Pego1.PePlot.Option.BestFitCoeffs[0, 1] >= 0)
24    t = t + "+ ";
25t = t + String.Format("{0:#.##}", Pego1.PePlot.Option.BestFitCoeffs[0, 1]) + "x ";
26if(Pego1.PePlot.Option.BestFitCoeffs[0, 0] >= 0)
27    t = t + "+ ";
28t = t + String.Format("{0:#.##}", Pego1.PePlot.Option.BestFitCoeffs[0, 0]);
29t = t + '\n'; // Line feed
30 
31// Second subset's coeffs. //
32t =  t + "Florida y = " + String.Format("{0:#.##}", Pego1.PePlot.Option.BestFitCoeffs[1, 3]) + "x^3 ";
33if(Pego1.PePlot.Option.BestFitCoeffs[1, 2] >= 0)
34    t = t + "+ ";
35t = t + String.Format("{0:#.##}", Pego1.PePlot.Option.BestFitCoeffs[1, 2]) + "x^2 ";
36if(Pego1.PePlot.Option.BestFitCoeffs[1, 1] >= 0)
37    t = t + "+ ";
38t = t + String.Format("{0:#.##}", Pego1.PePlot.Option.BestFitCoeffs[1, 1]) + "x ";
39if(Pego1.PePlot.Option.BestFitCoeffs[1, 0] >= 0)
40    t = t + "+ ";
41t = t + String.Format("{0:#.##}", Pego1.PePlot.Option.BestFitCoeffs[1, 0]);
42 
43// Put text into a line annotations //'
44Pego1.PeAnnotation.Line.YAxis[0] = Pego1.PeGrid.Configure.ManualMaxY - 1;
45//Pego1.PeAnnotation.Line.HorizontalType[0] = -1;  // no line, just text
46Pego1.PeAnnotation.Line.YAxisText[0] = t;
47 
48// Increases line annotation text size to max
49Pego1.PeFont.LineAnnotationTextSize = 100;
50Pego1.PeAnnotation.Show = true;
51 
52// Generally call ReinitializeResetImage at end **'
53Pego1.PeFunction.ReinitializeResetImage();
54Pego1.Invalidate();
55// Optionally call Pego1.Refresh() if you are not seeing changes immediately