private PolynomialFitResult PolynomialFit(long Number_Obs, double Time_First_JD, double[] SecondsFromTimeFirstJD,
double[] Variable_Star_DN, double[] Variable_Sky_DN, double[] Comparison_Star_DN,
double[] Comparison_Sky_DN,
int firstObsIndex, int lastObsIndex, double kweeVanWoerdenT0)
{
// http://var2.astro.cz/library/1350745528_ebfit.pdf
//
// Mag(t) = M0 + C1 * F(t, t0, d, G)
// F(t, t0, d, G) = 1 - {1 - Exp[1 - cosh((t - t0 / d))] } ^ G;
// t0 - time of minimum
// d > 0 is the minimum width
// G > 0 - the pointedness, G > 1 corresponds to flat minima (total eclipse)
//
// -----------------------------------------------------------------------------
//
// We use a simplified model:
//
// Mag(t) = M0 - C * {1 - Exp[1 - cosh((t - T0 / D))] } ^ G
//
// Where M0 is a constrant and we don't fit for it
// C has been fixed to +1
// t0 is taken from the KweeVanWoerden solution
// ------------------------------------------------------------------------------
var rv = new PolynomialFitResult();
rv.TimePoints = new List<double>();
var dataPointsVar = new List<double>();
var dataPointsComp = new List<double>();
for (int i = 0; i < Number_Obs; i++)
{
double y = (Variable_Star_DN[i] - Variable_Sky_DN[i]) / (Comparison_Star_DN[i] - Comparison_Sky_DN[i]);
if (i >= firstObsIndex && i < lastObsIndex)
{
double x = SecondsFromTimeFirstJD[i] / (24 * 3600);
rv.TimePoints.Add(x);
dataPointsVar.Add(Variable_Star_DN[i] - Variable_Sky_DN[i]);
dataPointsComp.Add(Comparison_Star_DN[i] - Comparison_Sky_DN[i]);
}
rv.DataPoints.Add(y);
}
var fitter = new ModelFitter(rv.TimePoints.Count, rv.TimePoints.ToArray(), dataPointsVar.ToArray(), dataPointsComp.ToArray());
fitter.Solve(true, kweeVanWoerdenT0);
for (int i = 0; i < Number_Obs; i++)
{
if (i >= firstObsIndex && i < lastObsIndex)
rv.FittedValues.Add(fitter.NormIntensities[i - firstObsIndex]);
else
rv.FittedValues.Add(double.NaN);
}
rv.G = fitter.G;
rv.M0 = fitter.M0;
rv.C = fitter.C;
rv.D = fitter.D;
rv.T0 = fitter.T0;
rv.StartIndex = firstObsIndex;
rv.StopIndex = lastObsIndex;
rv.Time_Of_Minimum_JD = Time_First_JD + fitter.T0;
rv.Time_Of_Minimum_Uncertainty = 0; // Math.Sqrt((4.0 * rv.A * rv.C - rv.B * rv.B) / (4.0 * rv.A * rv.A) / ((float)(rv.TimePoints.Count / 4.0 - 1.0)));
return rv;
}
private PolynomialFitResult PolynomialFit(long Number_Obs, double Time_First_JD, double[] SecondsFromTimeFirstJD,
double[] Variable_Star_DN, double[] Variable_Sky_DN, double[] Comparison_Star_DN,
double[] Comparison_Sky_DN,
int firstObsIndex, int lastObsIndex, double kweeVanWoerdenT0)
{
// http://var2.astro.cz/library/1350745528_ebfit.pdf
//
// Mag(t) = M0 + C1 * F(t, t0, d, G)
// F(t, t0, d, G) = 1 - {1 - Exp[1 - cosh((t - t0 / d))] } ^ G;
// t0 - time of minimum
// d > 0 is the minimum width
// G > 0 - the pointedness, G > 1 corresponds to flat minima (total eclipse)
//
// -----------------------------------------------------------------------------
//
// We use a simplified model:
//
// Mag(t) = M0 - C * {1 - Exp[1 - cosh((t - T0 / D))] } ^ G
//
// Where M0 is a constrant and we don't fit for it
// C has been fixed to +1
// t0 is taken from the KweeVanWoerden solution
// ------------------------------------------------------------------------------
var rv = new PolynomialFitResult();
rv.TimePoints = new List <double>();
var dataPointsVar = new List <double>();
var dataPointsComp = new List <double>();
for (int i = 0; i < Number_Obs; i++)
{
double y = (Variable_Star_DN[i] - Variable_Sky_DN[i]) / (Comparison_Star_DN[i] - Comparison_Sky_DN[i]);
if (i >= firstObsIndex && i < lastObsIndex)
{
double x = SecondsFromTimeFirstJD[i] / (24 * 3600);
rv.TimePoints.Add(x);
dataPointsVar.Add(Variable_Star_DN[i] - Variable_Sky_DN[i]);
dataPointsComp.Add(Comparison_Star_DN[i] - Comparison_Sky_DN[i]);
}
rv.DataPoints.Add(y);
}
var fitter = new ModelFitter(rv.TimePoints.Count, rv.TimePoints.ToArray(), dataPointsVar.ToArray(), dataPointsComp.ToArray());
fitter.Solve(true, kweeVanWoerdenT0);
for (int i = 0; i < Number_Obs; i++)
{
if (i >= firstObsIndex && i < lastObsIndex)
{
rv.FittedValues.Add(fitter.NormIntensities[i - firstObsIndex]);
}
else
{
rv.FittedValues.Add(double.NaN);
}
}
rv.G = fitter.G;
rv.M0 = fitter.M0;
rv.C = fitter.C;
rv.D = fitter.D;
rv.T0 = fitter.T0;
rv.StartIndex = firstObsIndex;
rv.StopIndex = lastObsIndex;
rv.Time_Of_Minimum_JD = Time_First_JD + fitter.T0;
rv.Time_Of_Minimum_Uncertainty = 0; // Math.Sqrt((4.0 * rv.A * rv.C - rv.B * rv.B) / (4.0 * rv.A * rv.A) / ((float)(rv.TimePoints.Count / 4.0 - 1.0)));
return(rv);
}
