Python Pandas 面试题与答案

问题 16. Explain the difference between Series and DataFrame in Pandas.

A Series is a one-dimensional labeled array, and a DataFrame is a two-dimensional table.

问题 17. How do you convert a Pandas DataFrame to a NumPy array?

Use the values attribute. df.values

问题 18. What is the purpose of the nunique function in Pandas?

nunique returns the number of unique elements in a Series or DataFrame.

Example:

df['column'].nunique()

问题 19. How can you reset the index of a Pandas DataFrame?

Use the reset_index function. df.reset_index()

问题 20. Explain the concept of MultiIndex in Pandas.

MultiIndex is used to represent hierarchical index levels in a DataFrame.