/* $Id: cpl_math_const.h,v 1.6 2007/09/14 09:46:54 llundin Exp $
 *
 * This file is part of the ESO Common Pipeline Library
 * Copyright (C) 2001-2004 European Southern Observatory
 *
 * 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 2 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/*
 * $Author: llundin $
 * $Date: 2007/09/14 09:46:54 $
 * $Revision: 1.6 $
 * $Name:  $
 */

#ifndef CPL_MATH_CONST_H
#define CPL_MATH_CONST_H

#include <cpl_macros.h>

CPL_BEGIN_DECLS

/**
 * @defgroup cpl_math Fundamental math functionality
 *
 * This module provides fundamental math constants.
 *
 * Source: On-Line Encyclopedia of Integer Sequences (OEIS)
 * pi:      http://www.research.att.com/~njas/sequences/A000796
 * e:       http://www.research.att.com/~njas/sequences/A001113
 * ln(2):   http://www.research.att.com/~njas/sequences/A002162
 * ln(10):  http://www.research.att.com/~njas/sequences/A002392
 *
 * The derived constants have been computed with the
 * GNU Multiple-Precision Library v. 4.2.2.
 *
 * The constants are listed with a precision that allows a one-line definition.
 *
 * @par Synopsis:
 * @code
 *   #include <cpl_math_const.h>
 * @endcode
 */

/**@{*/

/*-----------------------------------------------------------------------------
                                Defines
 -----------------------------------------------------------------------------*/

/* The base of the exponential function */
#define CPL_MATH_E        2.7182818284590452353602874713526624977572470936999595

/* The ratio of a circles circumference to its diameter */
#define CPL_MATH_PI       3.1415926535897932384626433832795028841971693993751058

/* The natural logarithm of 2 */
#define CPL_MATH_LN2      0.6931471805599453094172321214581765680755001343602553

/* The natural logarithm of 10 */
#define CPL_MATH_LN10     2.3025850929940456840179914546843642076011014886287730

/* Derived constants */
/* 2pi */
#define CPL_MATH_2PI      6.2831853071795864769252867665590057683943387987502116

/* pi/2 */
#define CPL_MATH_PI_2     1.5707963267948966192313216916397514420985846996875529

/* pi/4 */
#define CPL_MATH_PI_4     0.7853981633974483096156608458198757210492923498437765

/* 1/pi */
#define CPL_MATH_1_PI     0.3183098861837906715377675267450287240689192914809129

/* 2/pi */
#define CPL_MATH_2_PI     0.6366197723675813430755350534900574481378385829618258

/* 4/pi */
#define CPL_MATH_4_PI     1.2732395447351626861510701069801148962756771659236516

/* sqrt(2pi) */
#define CPL_MATH_SQRT2PI  2.5066282746310005024157652848110452530069867406099383

/* 2/sqrt(pi) */
#define CPL_MATH_2_SQRTPI 1.1283791670955125738961589031215451716881012586579977

/* sqrt(2) */
#define CPL_MATH_SQRT2    1.4142135623730950488016887242096980785696718753769481

/* sqrt(3) */
#define CPL_MATH_SQRT3    1.7320508075688772935274463415058723669428052538103806

/* sqrt(1/2) */
#define CPL_MATH_SQRT1_2  0.7071067811865475244008443621048490392848359376884740

/* log2(e) */
#define CPL_MATH_LOG2E    1.4426950408889634073599246810018921374266459541529859

/* log10(e) */
#define CPL_MATH_LOG10E   0.4342944819032518276511289189166050822943970058036666

/* 180/pi */
#define CPL_MATH_DEG_RAD  57.295779513082320876798154814105170332405472466564322

/* pi/180 */
#define CPL_MATH_RAD_DEG  0.0174532925199432957692369076848861271344287188854173

/* FWHM per Sigma, 2.0*sqrt(2.0*log(2.0)) */
#define CPL_MATH_FWHM_SIG 2.3548200450309493820231386529193992754947713787716411

/* Sigma per FWHM, 0.5/sqrt(2.0*log(2.0)) */
#define CPL_MATH_SIG_FWHM 0.4246609001440095213607514170514448098575705468921770

/**@}*/

CPL_END_DECLS

#endif