include/maths.h

   1 /*
   2  * $Id$
   3  *
   4  *                This source code is part of
   5  *
   6  *                 G   R   O   M   A   C   S
   7  *
   8  *          GROningen MAchine for Chemical Simulations
   9  *
  10  *                        VERSION 3.1
  11  * Copyright (c) 1991-2001, University of Groningen, The Netherlands
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
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  17  * If you want to redistribute modifications, please consider that
  18  * scientific software is very special. Version control is crucial -
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  31  */
  32
  33 #ifndef _maths_h
  34 #define _maths_h
  35
  36 #ifdef HAVE_CONFIG_H
  37 #include <config.h>
  38 #endif
  39
  40 #include <math.h>
  41 #include "typedefs.h"
  42
  43 #ifndef M_PI
  44 #define M_PI            3.14159265358979323846
  45 #endif
  46
  47 #ifndef M_PI_2
  48 #define M_PI_2          1.57079632679489661923
  49 #endif
  50
  51 #ifndef M_2PI
  52 #define M_2PI           6.28318530718
  53 #endif
  54
  55 #ifndef M_SQRT2
  56 #define M_SQRT2 sqrt(2.0)
  57 #endif
  58
  59 #ifdef CPLUSPLUS
  60 extern "C" {
  61 #endif
  62
  63 extern  int             gmx_nint(real a);
  64 extern  real            sign(real x,real y);
  65
  66 extern  real            gmx_erf(real x);
  67 extern  real            gmx_erfc(real x);
  68
  69 #ifdef CPLUSPLUS
  70 }
  71 #endif
  72
  73 #endif  /* _maths_h */