Python random.sample()用法及代码示例

sample()是Python中随机模块的内置函数，可返回从序列中选择的项目的特定长度列表，即列表，元组，字符串或集合。用于随机抽样而无需更换。

用法： random.sample(sequence, k)

参数：
sequence：可以是列表，元组，字符串或集合。
k：一个整数值，它指定样本的长度。

返回：k长度从序列中选择的新元素列表。

代码1：sample()函数的简单实现。

# Python3 program to demonstrate 
# the use of sample() function . 
  
# import random  
from random import sample 
  
# Prints list of random items of given length 
list1 = [1, 2, 3, 4, 5]  
  
print(sample(list1,3))

输出：

[2, 3, 5]

代码2：sample()函数的基本用法。

# Python3 program to demonstrate 
# the use of sample() function . 
  
# import random  
import random 
  
  
# Prints list of random items of 
# length 3 from the given list. 
list1 = [1, 2, 3, 4, 5, 6]  
print("With list:", random.sample(list1, 3)) 
  
# Prints list of random items of 
# length 4 from the given string.  
string = "GeeksforGeeks"
print("With string:", random.sample(string, 4)) 
  
# Prints list of random items of 
# length 4 from the given tuple. 
tuple1 = ("ankit", "geeks", "computer", "science", 
                   "portal", "scientist", "btech") 
print("With tuple:", random.sample(tuple1, 4)) 
  
  
# Prints list of random items of 
# length 3 from the given set. 
set1 = {"a", "b", "c", "d", "e"} 
print("With set:", random.sample(set1, 3))

输出：

With list:[3, 1, 2]
With string:['e', 'f', 'G', 'G']
With tuple:['ankit', 'portal', 'geeks', 'computer']
With set:['b', 'd', 'c']

注意：每次返回随机项目时，输出都会有所不同。

代码3：引发异常

如果样本大小(即k)大于序列大小，则会引发ValueError。

# Python3 program to demonstrate the 
# error of sample() function. 
import random 
  
list1 = [1, 2, 3, 4]  
   
# exception raised 
print(random.sample(list1, 5))

输出：

Traceback (most recent call last):
  File "C:/Users/user/AppData/Local/Programs/Python/Python36/all_prgm/geeks_article/sample_method_article.py", line 8, in 
    print(random.sample(list1, 5))
  File "C:\Users\user\AppData\Local\Programs\Python\Python36\lib\random.py", line 317, in sample
    raise ValueError("Sample larger than population or is negative")
ValueError:Sample larger than population or is negative

相关用法

注：本文由纯净天空筛选整理自AnkitRai01大神的英文原创作品 Python | random.sample() function。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。