private void DrawChebyshevTable()
{
float[] xValues = new float[]
{
-3.2f, -2.1f, 0.4f, 0.7f, 2.0f, 2.5f, 2.777f
};
float[] yValues = new float[]
{
10.0f, -2.0f, 0, -7.0f, 7.0f, 0, 0
};
float a = xValues[0];
float b = xValues[xValues.Length - 1];
var coefs = ChebyshevApproximation.Approximate(xValues, yValues, 0);
coefs = ChebyshevApproximation.Approximate(xValues, yValues, 1);
MnkK1Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(xValues, yValues, 2);
MnkK2Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(xValues, yValues, 3);
MnkK3Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(xValues, yValues, 4);
MnkK4Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(xValues, yValues, 5);
MnkK5Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(xValues, yValues, 6);
MnkK6Plotter.ItemsSource = GeneratePoints(coefs, a, b);
}
private void DrawChebyshevFunc()
{
var coefs = ChebyshevApproximation.Approximate(a, b, 1, ApproximatedFunction);
MnkK1Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(a, b, 2, ApproximatedFunction);
MnkK2Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(a, b, 3, ApproximatedFunction);
MnkK3Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(a, b, 4, ApproximatedFunction);
MnkK4Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(a, b, 5, ApproximatedFunction);
MnkK5Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(a, b, 6, ApproximatedFunction);
MnkK6Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(a, b, 7, ApproximatedFunction);
MnkK7Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(a, b, 8, ApproximatedFunction);
MnkK8Plotter.ItemsSource = GeneratePoints(coefs, a, b);
coefs = ChebyshevApproximation.Approximate(a, b, 9, ApproximatedFunction);
MnkK9Plotter.ItemsSource = GeneratePoints(coefs, a, b);
}
public void ApproximateTableValues()
{
float[] xValues = new float[]
{
-3.2f, -2.1f, 0.4f, 0.7f, 2.0f, 2.5f, 2.777f
};
float[] yValues = new float[]
{
10.0f, -2.0f, 0, -7.0f, 7.0f, 0, 0
};
var polynom = ChebyshevApproximation.Approximate(xValues, yValues, xValues.Length - 1);
Assert.That(polynom.Length == xValues.Length);
}
public void Approximate()
{
float a = -2.0f;
float b = 2.0f;
float step = 0.5f;
int rank = ChebyshevApproximation.CalculateRank(a, b, step);
var polynom = ChebyshevApproximation.Approximate(a, b, rank, myFunc);
List <float> results = new List <float>();
var xApprox = GenerateX(a, b, 0.0001f);
for (float i = a; i <= b; i += 0.0001f)
{
float x = ChebyshevApproximation.Squish(i, a, b);
results.Add(ChebyshevApproximation.Evaluate(polynom, x));
}
Assert.That(polynom.Length == rank + 1);
}
public void CompareTableAndFunc()
{
float a = -2.0f;
float b = 2.0f;
float step = 0.5f;
int rank = ChebyshevApproximation.CalculateRank(a, b, step);
var xValues = GenerateX(a, b, step);
var yValues = new float[rank];
for (int i = 0; i < rank; i++)
{
yValues[i] = (float)myFunc(xValues[i]);
}
var expectedCoefficients = new Matrix(ChebyshevApproximation.Approximate(a, b, rank - 1, myFunc));
var actualCoefficients = new Matrix(ChebyshevApproximation.Approximate(xValues, yValues, xValues.Length - 1));
Assert.That(actualCoefficients.NearEquals(expectedCoefficients, (float)Math.PI + 0.2f), $"Expected: {expectedCoefficients.ToString()}, actual {actualCoefficients.ToString()}");
}
private void DemoTable_Chebyshev_Click(object sender, RoutedEventArgs e)
{
CleanDataSources();
float[] xValues = new float[]
{
0, 3.3f, 6.6f, 9.9f
};
float[] yValues = new float[]
{
2.1f, 5.9f, 2.4f, 3.4f
};
var coefs = ChebyshevApproximation.Approximate(
xValues,
yValues,
1
);
MnkK1Plotter.ItemsSource = GeneratePoints(coefs, xValues[0], xValues[xValues.Length - 1]);
coefs = ChebyshevApproximation.Approximate(
xValues,
yValues,
2
);
MnkK2Plotter.ItemsSource = GeneratePoints(coefs, xValues[0], xValues[xValues.Length - 1]);
coefs = ChebyshevApproximation.Approximate(
xValues,
yValues,
3
);
MnkK3Plotter.ItemsSource = GeneratePoints(coefs, xValues[0], xValues[xValues.Length - 1]);
DrawBasePoints(xValues, yValues);
}