我试图从 Python 中的 URL 中提取数据，并在尝试查找最常见的数据源时遇到此错误

Question

这是我的代码

import pandas as pd

# Read the data from the Wikipedia page into a Pandas DataFrame
url = "https://en.wikipedia.org/wiki/List_of_countries_and_dependencies_by_population"
df = pd.read_html(url, attrs={"class": "wikitable"})[0]

# Visualize the DataFrame
print(df)

# Print the number of records in the DataFrame
print(f"There are {len(df)} records in the DataFrame.")


# Find the most common data source
most_common_source = df["Source"].value_counts().index[0]

print(f"The most common data source is {most_common_source}.")

KeyError Traceback（最近调用最后）/usr/local/lib/python3.8/dist-packages/pandas/core/indexes/base.py in get_loc(self, key, method, tolerance) 3360 try: -> 3361 return self._engine.get_loc(casted_key) 3362 除了 KeyError 作为错误：

8帧 pandas/_libs/hashtable_class_helper.pxi pandas._libs.hashtable.PyObjectHashTable.get_item()

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

KeyError：“来源”

上述异常是以下异常的直接原因：

KeyError Traceback（最后一次调用）/usr/local/lib/python3.8/dist-packages/pandas/core/indexes/base.py in get_loc(self, key, method, tolerance) 3361 return self._engine.get_loc (casted_key) 3362 除了 KeyError 为 err: -> 3363 raise KeyError(key) from err 3364 3365 if is_scalar(key) and isna(key) and not self.hasnans:

KeyError：“来源”

Answer 1

您尝试从中提取的表没有名为Source的列。 也许你的意思是这样的：

most_common_source = \
    df["Source (official or from the\xa0United Nations)"].value_counts().index[0]

您始终可以使用list(df.columns)打印您的列。