KeyError 更改数据框中的列

Question

我正在尝试更改列或处理列，但遇到一些 keyError 错误。致力于芝加哥犯罪数据分析。

例如，当我尝试运行

ds["DATE OF OCCURRENCE"] = pd.to_datetime([ds["DATE OF OCCURRENCE"]], format="%m/%d/%Y %I:%M:%S %p")

按键错误

Traceback (most recent call last)
/usr/local/lib/python3.6/dist-packages/pandas/core/indexes/base.py in get_loc(self, key, method, tolerance)

完整代码：

import pandas as pd
url="https://data.cityofchicago.org/api/views/x2n5-8w5q/rows.csv?accessType=DOWNLOAD"
df= pd.read_csv(url)
ds = df.copy()
ds["DATE OF OCCURRENCE"] = pd.to_datetime([ds["DATE OF OCCURRENCE"]], format="%m/%d/%Y %I:%M:%S %p")

这是错误：

2896 try: -> 2897 return self._engine.get_loc(key) 2898 except KeyError:

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

KeyError: 'DATE OF OCCURRENCE'

During handling of the above exception, another exception occurred:

KeyError Traceback (most recent call last) 2 frames /usr/local/lib/python3.6/dist-packages/pandas/core/indexes/base.py in get_loc(self, key, method, tolerance) 2897 return self._engine.get_loc(key) 2898 except KeyError: -> 2899 return self._engine.get_loc(self._maybe_cast_indexer(key)) 2900
indexer = self.get_indexer([key], method=method, tolerance=tolerance) 2901 if indexer.ndim > 1 or indexer.size > 1:

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas/_libs/index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

pandas/_libs/hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

KeyError: 'DATE OF OCCURRENCE'

Answer 1

您的专栏已重命名，因此 Crime_Date 和 select 专栏只有一个 [] 用于 Series:

ds["Crime_Date"] = pd.to_datetime(ds["Crime_Date"], format="%m/%d/%Y %I:%M:%S %p")

编辑：

列名中有一些空格，所以需要：

ds["DATE  OF OCCURRENCE"] = pd.to_datetime(ds["DATE  OF OCCURRENCE"], format="%m/%d/%Y %I:%M:%S %p")

KeyError 更改数据框中的列

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