random.h

书名:C语言科学与艺术,以前交钱下载的

/*
 * File: random.h
 * Last modified on Mon Sep 13 10:42:45 1993 by eroberts
 * --------------
 * Library package to produce pseudo-random numbers.
 */

#ifndef _random_h
#define _random_h

#include "genlib.h"

/*
 * Function: Randomize
 * Usage: Randomize();
 * -------------------
 * This function sets the random seed so that the random
 * sequence is unpredictable.  During the debugging phase,
 * it is best not to call this function, so that program
 * behavior is repeatable.
 */

void Randomize(void);

/*
 * Function: RandomInteger
 * Usage: n = RandomInteger(low, high);
 * ------------------------------------
 * This function returns a random integer in the range
 * low to high, inclusive.
 */

int RandomInteger(int low, int high);

/*
 * Function: RandomReal
 * Usage: d = RandomReal(low, high);
 * ---------------------------------
 * This function returns a random real number in the
 * half-open interval [low .. high), meaning that the
 * result is always greater than or equal to low but
 * strictly less than high.
 */

double RandomReal(double low, double high);

/*
 * Function: RandomChance
 * Usage: if (RandomChance(p)) . . .
 * ---------------------------------
 * The RandomChance function returns TRUE with the probability
 * indicated by p, which should be a floating-point number
 * between 0 (meaning never) and 1 (meaning always).  For
 * example, calling RandomChance(.30) returns TRUE 30 percent
 * of the time.
 */

bool RandomChance(double p);

#endif