/* glprng.h (pseudo-random number generator) */

/***********************************************************************

*  This code is part of GLPK (GNU Linear Programming Kit).

*

*  Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,

*  2009, 2010 Andrew Makhorin, Department for Applied Informatics,

*  Moscow Aviation Institute, Moscow, Russia. All rights reserved.

*  E-mail: <mao@gnu.org>.

*

*  GLPK 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 3 of the License, or

*  (at your option) any later version.

*

*  GLPK 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 GLPK. If not, see <http://www.gnu.org/licenses/>.

***********************************************************************/

#ifndef GLPRNG_H

#define GLPRNG_H

typedef struct RNG RNG;

struct RNG

{     /* Knuth's portable pseudo-random number generator */

      int A[56];

      /* pseudo-random values */

      int *fptr;

      /* the next A value to be exported */

};

#define rng_create_rand _glp_rng_create_rand

RNG *rng_create_rand(void);

/* create pseudo-random number generator */

#define rng_init_rand _glp_rng_init_rand

void rng_init_rand(RNG *rand, int seed);

/* initialize pseudo-random number generator */

#define rng_next_rand _glp_rng_next_rand

int rng_next_rand(RNG *rand);

/* obtain pseudo-random integer in the range [0, 2^31-1] */

#define rng_unif_rand _glp_rng_unif_rand

int rng_unif_rand(RNG *rand, int m);

/* obtain pseudo-random integer in the range [0, m-1] */

#define rng_delete_rand _glp_rng_delete_rand

void rng_delete_rand(RNG *rand);

/* delete pseudo-random number generator */

#define rng_unif_01 _glp_rng_unif_01

double rng_unif_01(RNG *rand);

/* obtain pseudo-random number in the range [0, 1] */

#define rng_uniform _glp_rng_uniform

double rng_uniform(RNG *rand, double a, double b);

/* obtain pseudo-random number in the range [a, b] */

#endif

/* eof */