Pandas 面试题与答案

问题 6. How to drop a column in a DataFrame?

You can drop a column using the drop() method: df.drop('ColumnName', axis=1, inplace=True)

问题 7. Explain the use of groupby() in Pandas.

groupby() is used to group DataFrame by a column and perform aggregate functions.

Example:

df.groupby('Column').mean()

问题 8. What is the purpose of the apply() function in Pandas?

apply() is used to apply a function along the axis of a DataFrame.

Example:

df['Column'].apply(lambda x: x*2)

问题 9. Explain the use of merge() in Pandas.

merge() is used to combine two DataFrames based on a common column.

Example:

pd.merge(df1, df2, on='common_column')

问题 10. How to handle missing values in a DataFrame?

You can use methods like dropna() to remove missing values or fillna() to fill them with a specific value.

Example:

df.dropna() or df.fillna(value)