Python随机模块

Python的随机模块是Python的内置模块，用于生成随机数。这些是伪随机数意味着这些不是真正的随机数。该模块可用于执行随机操作，例如生成随机数、为列表或字符串随机打印值等。

示例：打印列表中的随机值

Python3

# import random
import random
  
# prints a random value from the list
list1 = [1, 2, 3, 4, 5, 6]
print(random.choice(list1))

输出：

2

如上所述，随机模块创建伪随机数。随机数取决于播种值。例如，如果播种值为 5，则以下程序的输出将始终相同。

示例：使用种子值创建随机数

蟒蛇3

import random
  
random.seed(5)
  
print(random.random())
print(random.random())

输出：

0.6229016948897019
0.7417869892607294

上述代码的输出将始终相同。因此，它不得用于加密。

让我们讨论一些由该模块执行的常见操作。

创建随机整数

random.randint() 方法用于生成给定范围之间的随机整数。

句法 ：

randint(start, end)

示例：创建随机整数

蟒蛇3

# Python3 program explaining work
# of randint() function
  
# import random module
import random
  
# Generates a random number between
# a given positive range
r1 = random.randint(5, 15)
print("Random number between 5 and 15 is % s" % (r1))
  
# Generates a random number between
# two given negative range
r2 = random.randint(-10, -2)
print("Random number between -10 and -2 is % d" % (r2))

输出：

Random number between 5 and 15 is 7
Random number between -10 and -2 is -9

创建随机浮动

random.random() 方法用于生成 0.0 到 0.1 之间的随机整数。

句法：

random.random()

例子：

蟒蛇3

# Python3 program to demonstrate
# the use of random() function .
      
# import random
from random import random
      
# Prints random item
print(random())

输出：

0.3717933555623072

选择随机元素

random.choice()函数用于从列表、元组或字符串返回随机项。

句法：

random.choice(sequence)

示例：从列表、字符串和元组中选择随机元素

蟒蛇3

# Python3 program to demonstrate the use of
# choice() method
  
# import random
import random
  
# prints a random value from the list
list1 = [1, 2, 3, 4, 5, 6]
print(random.choice(list1))
  
# prints a random item from the string
string = "geeks"
print(random.choice(string))
  
# prints a random item from the tuple
tuple1 = (1, 2, 3, 4, 5)
print(random.choice(tuple1))

输出：

2
k
5

洗牌列表

random.shuffle() 方法用于打乱序列（列表）。洗牌意味着改变序列元素的位置。在这里，洗牌操作就位。

句法：

random.shuffle(sequence, function)

示例：混洗列表

蟒蛇3

# import the random module
import random
  
  
# declare a list
sample_list = [1, 2, 3, 4, 5]
  
print("Original list : ")
print(sample_list)
  
# first shuffle
random.shuffle(sample_list)
print("\nAfter the first shuffle : ")
print(sample_list)
  
# second shuffle
random.shuffle(sample_list)
print("\nAfter the second shuffle : ")
print(sample_list)

输出：

Original list : 
[1, 2, 3, 4, 5]

After the first shuffle : 
[4, 3, 5, 2, 1]

After the second shuffle : 
[1, 3, 4, 5, 2]

随机模块中所有函数的列表

Function Name	Description
seed()	Initialize the random number generator
getstate()	Returns an object with the current internal state of the random number generator
setstate()	Used to restore the state of the random number generator back to the specified state
getrandbits()	Return an integer with a specified number of bits
randrange()	Returns a random number within the range
randint()	Returns a random integer within the range
choice()	Returns a random item from a list, tuple, or string
choices()	Returns multiple random elements from the list with replacement
sample()	Returns a particular length list of items chosen from the sequence
random()	Generate random floating numbers
uniform()	Return random floating number between two numbers both inclusive
triangular()	Return a random floating point number within a range with a bias towards one extreme
betavariate()	Return a random floating point number with beta distribution
expovariate()	Return a random floating point number with exponential distribution
gammavariate()	Return a random floating point number with gamma distribution
gauss()	Return a random floating point number with Gaussian distribution
lognormvariate()	Return a random floating point number with log-normal distribution
normalvariate()	Return a random floating point number with normal distribution
vonmisesvariate()	Return a random floating point number with von Mises distribution or circular normal distribution
paretovariate()	Return a random floating point number with Pareto distribution
weibullvariate()	Return a random floating point number with Weibull distribution