#include <string.h>
#include <math.h>
#include <stdlib.h>
#include "random.h"

#define PCRAND
#ifdef PCRAND
#define RANDOM_MAX RAND_MAX
#else
#define RANDOM_MAX pow(2, 31)-1
#endif

/* this random function returns 1 if a random toss is within pfactor, 0<pfactor<1*/
int Probability(float pfactor)
  {
  return (pfactor>Random1());                                        
   /* if a random value from 0 to 1 is less than pfactor, return true*/
  }
/* -----------------------------------------------------------------------------------------------------------------*/
unsigned Random(unsigned num)                                /* returns a random word between 0 and num-1*/
  {
  float ratio, temp;
  
  ratio=num;
  temp=RANDOM_MAX;
  ratio=ratio/temp;
  #ifdef PCRAND
  temp=rand();
  #else
  temp=random();
  #endif
  if (temp*ratio>num-1) return num-1;
  else return (temp*ratio);
  }
/* ------------------------------------------------------------------------------------------------------------*/
/* returns a value between 0 and 1*/
float Random1(void)
  {
  float ratio,temp;

  #ifdef PCRAND
  ratio=rand();
  #else
  ratio=random();
  #endif
  temp=RANDOM_MAX;
  ratio=ratio/temp;
  if (ratio<=0) ratio=0.0001;
  if (ratio>=0.9999) ratio=0.9999;
  return ratio;
  }
/* -------------------------------------------------------------------------------------------------------------------*/
/* initializes random generator*/
void InitRandom(int seed)
  {
  #ifdef PCRAND
  srand(seed);
  #else
  static char state[64];

  initstate(seed,state,64);
  setstate(state);
  #endif
  }