gamma.h

来自「EM算法的改进」· C头文件 代码 · 共 38 行

/*
 * $Id: gamma.h 1339 2006-09-21 19:46:28Z tbailey $
 * 
 * $Log$
 * Revision 1.1  2005/07/29 18:38:01  nadya
 * Initial revision
 *
 */

/* 
	To compute the gamma function and the incomplete gamma function. 
*/

#ifndef GAMMA_H
#define GAMMA_H

#define ITMAX 100
#define EPS 1e-20

/* the incomplete gamma Q function */
#define GAMMAQ(a,x)	( ((x) < (a)+1) ? (1.0 - gser((a),(x))) : gcf((a),(x)))

extern double gser(
  double a, 
  double x
); 

extern double gcf(
  double a, 
  double x
);

extern double loggamma(
  double x
);
 
#endif