Variance Population

struct VariancePopulation

This structure uses the hyperparameters from the EfficiencyVector to generate the variance + associated derivatives.

Public Functions

inline VariancePopulation()

Default constructor.

inline VariancePopulation(double fraction, std::vector<double> contributions)

Constructor class

Parameters

• fraction – The value assigned to Fraction

• contributions – The vector assigned to Term

inline double Variance(double n)

Calculates the Variance contribution from this population

Parameters

n – The variance scaling parameter

Returns

v a guaranteed positive number

inline double dVariancedN(double n)

Calculates the derivative of the Variance with respect to the scaling parameter

Parameters

n – The variance scaling parameter

Returns

The analytical derivative of the variance

inline double dVariancedAlpha(int term, double n)

Calculates the derivative of the variance with respect to the ith-order Term parameter

Parameters

• term – the order of the parameter with which the derivative is taken

• n – The variance scaling parameter

Returns

dv/d alpha_term

Public Members

double Fraction

The fraction of stars which belong to this population.

std::vector<double> Term

A list of the (unconstrained) prefactors within the polynomial expansion.