Factorial, Gamma and related functions

Functions
double	factln (double n)
	Log-factorial . More...
dvector	factln (const dvector &r)
	Log-factorial of an array. More...
double	gammln (double xx)
	Log gamma function. More...
dvector	gammln (const dvector &v)
	Log-Gamma of an array. More...
double	log_comb (double n, double k)
	Log of the binomial coefficent; i.e log of 'n choose k'. More...
dvector	log_comb (const dvector &n, const dvector &r)
	Log-binomial of two arrays. More...

Detailed Description

Function Documentation

double factln

(

double

n

)

Log-factorial .

Parameters

n

a number

Returns

log of the factorial

Definition at line 38 of file combc.cpp.

Referenced by log_comb().

dvector factln

(

const dvector &

r

)

Log-factorial of an array.

Parameters

r

an array

Returns

log of the factorial

Definition at line 137 of file combc.cpp.

double gammln

(

double

xx

)

Log gamma function.

Parameters

xx

Returns

The implementation of this algorithm was inspired by "Numerical Recipes in C", 2nd edition, Press, Teukolsky, Vetterling, Flannery, chapter 6

Definition at line 52 of file combc.cpp.

Referenced by beta(), betai(), dbeta(), density_negbinomial(), dgamma(), dinvgamma(), dmultinom(), dnbinom(), dpois(), dstudent_t(), dzinbinom(), factln(), gamma_density(), gammln(), gcf(), get_initial_u(), gser(), inv_cumd_gamma(), lgamma(), lnbeta(), log_density_negbinomial(), log_density_poisson(), log_gamma_density(), log_negbinomial_density(), negbinomial_density(), nllBeta(), nllDirichlet(), nllGamma(), nllInverseGamma(), nllMultiNomial(), nllNegativeBinomial(), nllPoisson(), pbeta(), and randpoisson().

dvector gammln

(

const dvector &

v

)

Log-Gamma of an array.

Parameters

v

an array

Returns

log of the factorial

Definition at line 119 of file combc.cpp.

double log_comb	(	double	n,
		double	k
	)

Log of the binomial coefficent; i.e log of 'n choose k'.

Parameters

n	a number
k	a number

Returns

Definition at line 27 of file combc.cpp.

Referenced by dbinom(), log_comb(), and nllBinomial().

dvector log_comb	(	const dvector &	n,
		const dvector &	r
	)

Log-binomial of two arrays.

Parameters

n	an array
r	an array

Returns

log of the binomial coefficent

Definition at line 77 of file combc.cpp.