spot/lbtt/src/Random.h
Alexandre Duret-Lutz 15618b84ea Import of lbtt 1.0.3
2004-02-16 11:35:59 +00:00

96 lines
3.1 KiB
C

/*
* Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004
* Heikki Tauriainen <Heikki.Tauriainen@hut.fi>
*
* 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.
*/
#ifndef RANDOM_H
#define RANDOM_H
#include <config.h>
#include <cstdlib>
#ifdef HAVE_RAND48
#define rand lrand48
#define srand srand48
static const double MAXRAND = static_cast<double>(1 << 30) * 2.0;
#else
static const double MAXRAND = RAND_MAX + 1.0;
#endif /* HAVE_RAND48 */
/******************************************************************************
*
* Functions for random number generation. If HAVE_RAND48 is defined, the
* functions rely on the lrand48() function for generating a random integer
* between 0 and 2^31 and srand48() for setting the seed for the random
* number generator; otherwise, the rand() and srand() functions are used,
* respectively.
*
*****************************************************************************/
/* ========================================================================= */
inline void SRAND(unsigned int seed)
/* ----------------------------------------------------------------------------
*
* Description: Initializes the random number generator with a seed value.
*
* Argument: seed -- Seed for the random number generator.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
srand (seed);
}
/* ========================================================================= */
inline double DRAND()
/* ----------------------------------------------------------------------------
*
* Description: Generates a random double.
*
* Arguments: None.
*
* Returns: A random double in the half-open interval [0.0,1.0).
*
* ------------------------------------------------------------------------- */
{
return rand () / MAXRAND;
}
/* ========================================================================= */
inline long int LRAND(long int min, long int max)
/* ----------------------------------------------------------------------------
*
* Description: Generates a random long integer in a given interval.
*
* Arguments: min, max -- Bounds for the interval.
*
* Returns: A random long integer in the half-open interval [min,max).
*
* ------------------------------------------------------------------------- */
{
return min + static_cast<long int>(DRAND() * (max - min));
}
#ifdef HAVE_RAND48
#undef rand
#undef srand
#endif /* HAVE_RAND48 */
#endif /* !RANDOM_H */