TypeError: Cannot perform 'ror_' with a dtyped [float64] array and scalar of type [bool]

Question

我想遍历 df['fyear'] 列并删除 fyear 不等于 2009、2019 或 2020 的任何行。但是出现此错误：

TypeError: Cannot perform 'ror_' with a dtyped [float64] array and scalar of type [bool]

df = pd.DataFrame({'fyear': [2009, 2019, 2020, 2020, 2019, 2009, 2000, 2000, 2001]})

for row in df.iterrows():
    if df["fyear"] != 2009 | df["fyear"] !=2019 | df["fyear"] !=2020:
        df.drop(row)

EDIT 最佳解决方案是使用运算符 & 或 |

的布尔索引

df = df[(df['fyear'] == 2009) | (df['fyear'] == 2019) | (df['fyear'] == 2020)]

Answer 1

Python 使用 or 作为中缀关键字

df["fyear"] != 2009 or df["fyear"] !=2019 or df["fyear"] !=2020

甚至更好（更 pythonic 且可读）

df["fyear"] not in (2009,2019,2020)

TypeError: Cannot perform 'ror_' with a dtyped [float64] array and scalar of type [bool]

TypeError: Cannot perform 'ror_' with a dtyped [float64] array and scalar of type [bool]

python

iteration

boolean

dataframe

pandas