/* random.apb : random number utilities. */

/* Procedure to initialize the seed value. */
randomize()
{
    void srand48();    /* Initialization entry point. */
    long now;

    srand48 (time(&now));  /* Initialize the seed value. */
}

/* Function to return a single real value between 0.0 and 1.0. */
double random()
{
    double drand48();  /* Random number generator. */

    return (drand48());
}

/* Function to return a simulated biased coin toss (true = head). */
boolean flip (probability)
    double probability; 
{
    if (probability == 1.0)
        return (TRUE);
    else
        return ((random() <= probability));
}

/* Function to return an integer selected uniformly and pseudorandomly between upper and lower limits. */
int rnd (low, high)
    int low, high;
{
    double f, drand48();
    int i;
    
    if (low >= high)
        i = low;
    else
    {
        f = (drand48() * (high - low + 1) + low);
        i = (int) floor (f);
    }
    return (i);
}