python開發_random

和java中的random()函數一樣，在python中也有類似的模塊random，即隨機數

下面是我做的demo

運行效果：

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代碼部分：

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#python random

import random

def get_random():
    '''get a random number.
    return Random float x, 0.0 <= x < 1.0'''
    return random.random()

def get_uniform(a, b):
    '''Return a random floating point number N such that
    a <= N <= b for a <= b and b <= N <= a for b < a.
    The end-point value b may or may not be included in the
    range depending on floating-point rounding in the
    equation a + (b-a) * random().
    '''
    return random.uniform(a, b)

def get_randrange(n):
    '''return an Integer from 0 to n
    and the number n must be greater than 0
    or n > 0
    '''
    return random.randrange(n)

def get_randrange_ex(start, stop, step):
    '''返回一個從start開始到stop結束，步長為step的隨機數'''
    return random.randrange(start, stop, step)

def choice(s):
    '''從一個字符串中隨機獲取一個字符串，傳入的參數s是不能為空或者不能為None'''
    if s != '' and s != None:
        return random.choice(s)
    else:
        print('the param is empty or equals None!')

def shuffle(items):
    '''對一個序列進行洗牌的操作'''
    random.shuffle(items)
    return items

def sample(items, n):
    '''從一個序列中隨機抽出n個數，當然，在這n個數中，可能出現有重復的數'''
    return random.sample(items, n)

def main():
    r = get_random()
    print('獲取一個0.0-1.0之間的隨機數：{}'.format(r))
    r = get_uniform(2, 100)
    print('獲取一個2.0-100.0之間的隨機數：{}'.format(r))
    r = get_randrange(100)
    print('獲取一個0-100之間的隨機數：{}'.format(r))
    r = get_randrange_ex(3, 100, 25)
    print('獲取一個3-100之間的隨機數：{}'.format(r))
    tem_str = 'this is a test message!'
    r = choice(tem_str)
    print('從[{}]中隨機取出一個字符：{}'.format(tem_str, r))
    tem_items = [1, 2, 3, 4, 5, 6, 7]
    tem_r = tem_items[:]
    shuffle(tem_items)
    print('對序列{}進行洗牌操作：{}'.format(tem_r, tem_items))

    tem_list = sample(tem_r, 3)
    print('從{}中隨機抽出3個數：{}'.format(tem_r, tem_list))

if __name__ == '__main__':
    main()