src/include/R_ext/Constants.h

/*
 *  R : A Computer Language for Statistical Data Analysis
 *  Copyright (C) 1995, 1996  Robert Gentleman and Ross Ihaka
 *  Copyright (C) 1998-2022   The R Core Team.
 *
 *  This header file is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published by
 *  the Free Software Foundation; either version 2.1 of the License, or
 *  (at your option) any later version.
 *
 *  This file is part of R. R is distributed under the terms of the
 *  GNU General Public License, either Version 2, June 1991 or Version 3,
 *  June 2007. See doc/COPYRIGHTS for details of the copyright status of R.
 *
 *  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 Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program; if not, a copy is available at
 *  https://www.R-project.org/Licenses/
 */

/* Included by R.h: API */

#ifndef R_EXT_CONSTANTS_H_
#define R_EXT_CONSTANTS_H_

/* usually in math.h, but not with strict C99/C++11 compliance */
#ifndef M_PI
#define M_PI 3.141592653589793238462643383279502884197169399375
#endif

/*
  S-compatibility defines.
 */
#ifndef STRICT_R_HEADERS
#define PI             M_PI
#ifdef __cplusplus
#include <cfloat>   /* Defines the RHSs, C++11 and later */
#else
#include <float.h>  /* Defines the RHSs, C99 and later */
#endif

// The DOUBLE_* defines were deprecated in R 4.2.0
#define DOUBLE_DIGITS  DBL_MANT_DIG
#define DOUBLE_EPS     DBL_EPSILON
#define DOUBLE_XMAX    DBL_MAX
#define DOUBLE_XMIN    DBL_MIN
#endif

#endif /* R_EXT_CONSTANTS_H_ */