Python错误集锦： 调用random.choice()发生IndexError: Cannot choose from an empty sequence

原文链接：http://www.juzicode.com/python-error-random-choice-indexerror-cannot-choose-from-an-empty-sequence/

错误提示：

 调用random.choice()发生IndexError: Cannot choose from an empty sequence

#juzicode.com / vx公众号:桔子code
import  random
seed=[]
num = random.choice(seed)
print('random num=',num)

==========运行结果：
---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
<ipython-input-33-59aa68b0370d> in <module>
      2 import  random
      3 seed=[]
----> 4 num = random.choice(seed)
      5 print('random num=',num)

d:\python\python38\lib\random.py in choice(self, seq)
    288             i = self._randbelow(len(seq))
    289         except ValueError:
--> 290             raise IndexError('Cannot choose from an empty sequence') from None
    291         return seq[i]
    292 

IndexError: Cannot choose from an empty sequence

 

错误原因：

1、作为random.choice()入参的“种子”序列为空，导致IndexError 

解决方法：

1、用非空列表、元组、字符串等赋值seed变量

#juzicode.com / vx公众号:桔子code
import  random
seed=[1,2,3,5,6,7,8,9,0]
num = random.choice(seed)
print('random num=',num)
seed=(1.0,2.2,3.3,4.4,5.5,6.6,7.7,8.8,9.9)
num = random.choice(seed)
print('random num=',num)
seed='abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'
num = random.choice(seed)
print('random num=',num)

==========运行结果：
random num= 6 
random num= 5.5 
random num= V

扩展内容：

 

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