include/random.h

   1 /*
   2  *
   3  *                This source code is part of
   4  *
   5  *                 G   R   O   M   A   C   S
   6  *
   7  *          GROningen MAchine for Chemical Simulations
   8  *
   9  *                        VERSION 3.2.0
  10  * Written by David van der Spoel, Erik Lindahl, Berk Hess, and others.
  11  * Copyright (c) 1991-2000, University of Groningen, The Netherlands.
  12  * Copyright (c) 2001-2004, The GROMACS development team,
  13  * check out http://www.gromacs.org for more information.
  14
  15  * This program is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU General Public License
  17  * as published by the Free Software Foundation; either version 2
  18  * of the License, or (at your option) any later version.
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  20  * If you want to redistribute modifications, please consider that
  21  * scientific software is very special. Version control is crucial -
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  35
  36 #ifndef _random_h
  37 #define _random_h
  38
  39 #ifdef HAVE_CONFIG_H
  40 #include <config.h>
  41 #endif
  42
  43 #include <typedefs.h>
  44
  45 #ifdef __cplusplus
  46 extern "C" {
  47 #endif
  48
  49 extern int make_seed(void);
  50 /* Make a random seed: (time+getpid) % 1000000 */
  51
  52 extern real rando(int *seed);
  53 /* Generate a random number 0 <= r < 1. seed is the (address of) the
  54  * random seed variable.
  55  */
  56
  57 extern void maxwell_speed(real tempi,int seed,
  58                           gmx_mtop_t *mtop, rvec v[]);
  59 /* Generate velocites according to a maxwellian distribution */
  60
  61 extern real calc_cm(FILE *log,int natoms,real mass[],rvec x[],rvec v[],
  62                     rvec xcm,rvec vcm,rvec acm,matrix L);
  63 /* Calculate the c.o.m. position, velocity, acceleration and the
  64  * moment of Inertia. Returns the total mass.
  65  */
  66
  67 extern void stop_cm(FILE *log,int natoms,real mass[],rvec x[],rvec v[]);
  68
  69 #ifdef __cplusplus
  70 }
  71 #endif
  72
  73 #endif  /* _random_h */