/// @return double contribution to chi^2 sum against
/// a theoretical function
/// @param wp WeightedPoint
public double Chi2Contribution(WeightedPoint wp)
{
double residue = _yValue - wp.YValue;
return residue * residue / (1 / wp.Weight + 1 / _weight);
}
/// @param pdf DhbStatistics.ScaledProbabilityDensityFunction
/// @return double chi2 of histogram compared to supplied
/// probability distribution.
public double Chi2Against(ScaledProbabilityDensityFunction pdf)
{
double chi2 = 0;
for (int i = 0; i < _contents.Length; i++)
chi2 += new WeightedPoint(1, _contents[i]).Chi2Contribution(pdf);
return chi2;
}