public static void FitOrigin(double[] x, double[] y, double[] sig,
out double b, out double sigb, out double chi2, out double q)
{
int ndata = x.Length;
if (x.Length != y.Length)
{
throw new Exception("x.Length != y.Length: " + x.Length + " " + y.Length);
}
if (sig != null && x.Length != sig.Length)
{
throw new Exception("x.Length != sig.Length: " + x.Length + " " + sig.Length);
}
double t;
double st2 = 0.0;
b = 0.0;
if (sig != null)
{
for (int i = 0; i < ndata; i++)
{
t = (x[i]) / sig[i];
st2 += t * t;
b += t * y[i] / sig[i];
}
}
else
{
for (int i = 0; i < ndata; i++)
{
t = x[i];
st2 += t * t;
b += t * y[i];
}
}
b /= st2;
sigb = Math.Sqrt(1.0 / st2);
chi2 = 0.0;
if (sig == null)
{
for (int i = 0; i < ndata; i++)
{
double tmp = y[i] - b * x[i];
chi2 += tmp * tmp;
}
q = 1.0;
double sigdat = Math.Sqrt((chi2) / (ndata - 2));
sigb *= sigdat;
}
else
{
for (int i = 0; i < ndata; i++)
{
double tmp = (y[i] - b * x[i]) / sig[i];
chi2 += tmp * tmp;
}
q = NumericalRecipes.Gammq(0.5 * (ndata - 1), 0.5 * (chi2));
}
}
public static double Errfunc(double z)
{
try {
return((NumericalRecipes.Erffc(z / Math.Sqrt(2.0))) / 2.0);
} catch (Exception) {
return(1);
}
}
public static double[] DiagonalizeSymmMatrix(double[,] m, out double[,] evec)
{
double[] d;
double[] e;
evec = (double[, ])m.Clone();
NumericalRecipes.Tred2(evec, out d, out e);
NumericalRecipes.Tqli(d, e, evec);
return(d);
}
public static double LnMultinomial(int a, int[] bs)
{
double result = NumericalRecipes.Gammln(a + 1);
for (int i = 0; i < bs.Length; i++)
{
result -= NumericalRecipes.Gammln(bs[i] + 1);
}
return(result);
}
public static void LinFit2(double[] x, double[] y, double[] sig, double[] a,
out double chisq, LfitFunc funcs)
{
double[,] covar;
if (sig == null)
{
sig = new double[x.Length];
for (int i = 0; i < sig.Length; i++)
{
sig[i] = 1E-2;
}
}
NumericalRecipes.Lfit(x, y, sig, a, out covar, out chisq, funcs);
}
public static void FitNonlin(double[] x, double[] y, double[] sig, double[] a,
out double chisq, MrqminFunc func)
{
int ndata = x.Length;
if (sig == null)
{
sig = new double[ndata];
for (int i = 0; i < sig.Length; i++)
{
sig[i] = 1;
}
}
int ma = a.Length;
double[,] covar = new double[ma, ma];
double[,] alpha = new double[ma, ma];
int[] ia = new int[ma];
for (int i = 0; i < ma; i++)
{
ia[i] = 1;
}
double alamda = -1;
double ochisq = 0;
double[,] oneda = null;
int mfit = 0;
double[] atry = null;
double[] beta = null;
double[] da = null;
NumericalRecipes.Mrqmin(x, y, sig, ndata, a, ia, ma, covar, alpha, out chisq, func, ref alamda, ref ochisq,
ref oneda, ref mfit, ref atry, ref beta, ref da);
int count1 = 0;
while (alamda > 1e-20 && alamda < 1e20 && count1 < 100)
{
NumericalRecipes.Mrqmin(x, y, sig, ndata, a, ia, ma, covar, alpha, out chisq, func, ref alamda, ref ochisq,
ref oneda, ref mfit, ref atry, ref beta, ref da);
count1++;
}
alamda = 0;
NumericalRecipes.Mrqmin(x, y, sig, ndata, a, ia, ma, covar, alpha, out chisq, func, ref alamda, ref ochisq,
ref oneda, ref mfit, ref atry, ref beta, ref da);
}
