Question

不确定如何使用.bool（），any，all或empty来使两个不同的示例有效。每个都抛出了模糊值错误

import pandas as pd


first = pd.Series([1,0,0])
second = pd.Series([1,2,1])

number_df = pd.DataFrame( {'first': first,  'second': second} )

bool_df = pd.DataFrame( {'testA': pd.Series([True, False, True]), 'testB': pd.Series([True, False, False])})

#ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all(). 

""" both the next two lines fail with the ambiguous Series issue"""
#each row should be true or false 
bool_df['double_zero_check'] = (number_df['first'] != 0) and (number_df['second'] != 0 )
bool_df['parity'] = bool_df['testA'] and bool_df['testB']

Answer 1

你需要使用按位和（&）来逐行比较系列 - 更多docs

In [3]: bool_df['double_zero_check'] = (number_df['first'] != 0) & (number_df['second'] != 0 )

In [4]: bool_df['parity'] = bool_df['testA'] & bool_df['testB']

In [5]: bool_df
Out[5]: 
   testA  testB double_zero_check parity
0   True   True              True   True
1  False  False             False  False
2   True  False             False  False

Answer 2

您必须使用按位和（＆amp;）运算符。 and适用于布尔值，不适用于Pandas系列。

bool_df['double_zero_check'] = (number_df['first'] != 0) & (number_df['second'] != 0 )
bool_df['parity'] = bool_df['testA'] & bool_df['testB']

pandas系列元素布尔检查是ambigious

2 个答案: