首页 > 解决方案 > Pandas Apply Lambda 导致 TypeError: 'int' object is not subscriptable

问题描述

我有这个数据框的一个样本在这里:

块引用

我在处理这段代码时遇到了问题。我收到以下错误消息:

Traceback (most recent call last):   File "C:/Users/....py", line 12, in <module>
 dfF['CCRYear'] = dfF['Year'].apply(lambda x: 'True' if x['Year'] == x['MaxSS Year'] else 'False')   File "C:\Users\....py", line 3848, in apply
 mapped = lib.map_infer(values, f, convert=convert_dtype)   File "pandas\_libs\lib.pyx", line 2329, in pandas._libs.lib.map_infer   
 File "C:/Users/....py", line 12, in <lambda>
 dfF['CCRYear'] = dfF['Year'].apply(lambda x: 'True' if x['Year'] == x['MaxSS Year'] else 'False')
 TypeError: 'int' object is not subscriptable

'Year' 和 'MaxSS Year' 列都是 int64 数据类型。所以这是我下面的代码:

import pandas as pd
import numpy as np

def cached_date_parser(s):
    if s in cache:
        return cache[s]
    dt = pd.to_datetime(s, format='%Y%m%d', coerce=True)
    cache[s] = dt
    return dt

dfF = pd.read_csv(r'C:\\Users\\....C_14.csv', parse_dates = [1], header='infer')
dfF['CCRYear'] = dfF['Year'].apply(lambda x: 'True' if x['Year'] == x['MaxSS Year'] else 'False')

标签: pythondataframelambda

解决方案


您的代码的问题是您apply()在单个列上使用并且您正在为其编制索引。

看看你在做什么,只需x在你的lambda

df['Year'].apply(lambda x: print(x))

它会在下面输出

2017
2018
2018
2015
2015
2015

您的代码正在尝试索引整数值x['Year']。这x是整数年,如 2018 年、2019 年等。

将此更改为

dfF['CCRYear'] = dfF['Year'].apply(lambda x: 'True' if x['Year'] == x['MaxSS Year'] else 'False')

这个

dfF['CCRYear'] = dfF['Year'] == dfF['MaxSS Year']

使用np.where()

dfF['CCRYear'] = np.where(dfF['Year'] == dfF['MaxSS Year'], 'True', 'False')

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