rand.h

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/* RAND.H - Interface to random number generation procedures. */

/* Copyright (c) 1995, 2000, 2001 by Radford M. Neal 
 *
 * Permission is granted for anyone to copy, use, or modify this program 
 * for purposes of research or education, provided this copyright notice 
 * is retained, and note is made of any changes that have been made. 
 *
 * This program is distributed without any warranty, express or implied.
 * As this program was written for research purposes only, it has not been
 * tested to the degree that would be advisable in any important application.
 * All use of this program is entirely at the user's own risk.
 */

#ifndef RAND_H
#define RAND_H

/* STATE OF RANDOM NUMBER GENERATOR. */

#define N_tables 5		/* Number of tables of real random numbers */

typedef struct
{ int seed;			/* Seed state derives from */
  int ptr[N_tables];		/* Pointers for tables of real random numbers */
  unsigned short state48[3];	/* State of 'rand48' pseudo-random generator */
} rand_state;

typedef enum sp_make_method
{ Evencol, 	/* Uniform number of bits per column, with number specified */
  Evenboth 	/* Uniform (as possible) over both columns and rows */
} sp_make_method; 

typedef enum { Sparse, Dense, Mixed } gen_make_method;      /* Ways of making it */

struct	rand_sp_parmt
{
	int chk_num;	//times to check a bit
	int pos_no;		//row or col no.
};	

struct	rand_sp_pos
{
	int row;		//row no. to check a bit
	int col;		//col no. to check a bit
};	

struct rand_sp_pos *chk_pos;	//the positions of 1s in sp_matrix

/* BASIC PSEUDO-RANDOM GENERATION PROCEDURES. */

int rand_int(int, int);

void rand_int_num( int * , int, int);

double rand_uniopen (int);
double rand_uniform (int);
void rand01( int *data, int ,int);
void markov_symbol(int *symbol, int symbollength,double p);
double rand_gaussian (int);
double rand_logistic (int);
float uniform(int *seed);
void gen_symbol(int *symbol, int symbollength,double p[],int size);


void rand_seed( int);
static void initialize (void);

#endif