AlgGamma

Files
file	AlgGamma.c
	Functions for computing gamma and incomplete gamma functions.

Functions
double	AlgGammaLog (double x, AlgError *dstErr)
	Computes the log gamma function log(Gamma(x)), ie exp(AlgGammaLog(n + 1)) = n!. This function is based on the function gammln(): Press W. H., Teukolsky S. A., Vetterling W. T. and Flannery B. P, Numerical Recipies in C, 1992, CUP. More...
double	AlgGammaP (double a, double x, AlgError *dstErr)
	Computes the incomplete gamma function P(a,x), which has the limiting values P(a,0) = 0, P(a, oo) = 1.. This function is based on the function gammp(): Press W. H., Teukolsky S. A., Vetterling W. T. and Flannery B. P, Numerical Recipies in C, 1992, CUP. More...

Detailed Description

Function Documentation

double AlgGammaLog	(	double	x,
		AlgError *	dstErr
	)

Computes the log gamma function log(Gamma(x)), ie exp(AlgGammaLog(n + 1)) = n!. This function is based on the function gammln(): Press W. H., Teukolsky S. A., Vetterling W. T. and Flannery B. P, Numerical Recipies in C, 1992, CUP.

Returns

Log of gamma function value.

Parameters

x	Given value.
dstErr	Destination ptr for error code, may be NULL.

References ALG_ERR_FUNC, and ALG_ERR_NONE.

Referenced by AlgGammaP().

double AlgGammaP	(	double	a,
		double	x,
		AlgError *	dstErr
	)

Computes the incomplete gamma function P(a,x), which has the limiting values P(a,0) = 0, P(a, oo) = 1.. This function is based on the function gammp(): Press W. H., Teukolsky S. A., Vetterling W. T. and Flannery B. P, Numerical Recipies in C, 1992, CUP.

Returns

Incomplete gamma function value.

Parameters

a	Incomplete gamma fn parameter.
x	Incomplete gamma fn parameter.
dstErr	Destination ptr for error code, may be NULL.

References ALG_ERR_CONVERGENCE, ALG_ERR_FUNC, ALG_ERR_NONE, and AlgGammaLog().

Referenced by AlgLinearFit1D(), and AlgLinearFitIdx1D().