/* specfunc/gsl_sf_erf.h

 * 

 * Copyright (C) 1996, 1997, 1998, 1999, 2000 Gerard Jungman

 * 

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 3 of the License, or (at

 * your option) any later version.

 * 

 * This program is distributed in the hope that it will be useful, but

 * WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * General Public License for more details.

 * 

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

 */

/* Author:  G. Jungman */

#ifndef __GSL_SF_ERF_H__

#define __GSL_SF_ERF_H__

#include <gsl/gsl_sf_result.h>

#undef __BEGIN_DECLS

#undef __END_DECLS

#ifdef __cplusplus

# define __BEGIN_DECLS extern "C" {

# define __END_DECLS }

#else

# define __BEGIN_DECLS /* empty */

# define __END_DECLS /* empty */

#endif

__BEGIN_DECLS

/* Complementary Error Function

 * erfc(x) := 2/Sqrt[Pi] Integrate[Exp[-t^2], {t,x,Infinity}]

 *

 * exceptions: none

 */

int gsl_sf_erfc_e(double x, gsl_sf_result * result);

double gsl_sf_erfc(double x);

/* Log Complementary Error Function

 *

 * exceptions: none

 */

int gsl_sf_log_erfc_e(double x, gsl_sf_result * result);

double gsl_sf_log_erfc(double x);

/* Error Function

 * erf(x) := 2/Sqrt[Pi] Integrate[Exp[-t^2], {t,0,x}]

 *

 * exceptions: none

 */

int gsl_sf_erf_e(double x, gsl_sf_result * result);

double gsl_sf_erf(double x);

/* Probability functions:

 * Z(x) :  Abramowitz+Stegun 26.2.1

 * Q(x) :  Abramowitz+Stegun 26.2.3

 *

 * exceptions: none

 */

int gsl_sf_erf_Z_e(double x, gsl_sf_result * result);

int gsl_sf_erf_Q_e(double x, gsl_sf_result * result);

double gsl_sf_erf_Z(double x);

double gsl_sf_erf_Q(double x);

/* Hazard function, also known as the inverse Mill's ratio.

 *

 *   H(x) := Z(x)/Q(x)

 *         = Sqrt[2/Pi] Exp[-x^2 / 2] / Erfc[x/Sqrt[2]]

 *

 * exceptions: GSL_EUNDRFLW

 */

int gsl_sf_hazard_e(double x, gsl_sf_result * result);

double gsl_sf_hazard(double x);

__END_DECLS

#endif /* __GSL_SF_ERF_H__ */