Question

Which function is used to sort a Pandas DataFrame in descending order based on a column?

• A. df.sort_values(by='column_name', ascending=False)
• B. df.sort(by='column_name', order='desc')
• C. df.order_by('column_name', reverse=True)
• D. df.sort_data('column_name', descending=True)

Hint:

The parameter "ascending=False" is standard across SQL and Pandas.
Make sure to use the exact function "sort_values" instead of "sort".

Answer 1

The Correct Option is A

Step 1: Understanding the Question:
The question asks for the correct Pandas method and arguments to sort the rows of a DataFrame in descending order based on values in a specified column.

Step 2: Key Formula or Approach:
In Pandas, the function sort_values() is the built-in method to sort a DataFrame.
The key parameters are:
- by: Specifies the column name(s) to sort by.
- ascending: A boolean parameter. Setting it to False sorts the data in descending order. By default, it is True.

Step 3: Detailed Explanation:
Let's evaluate the options:
- Option (A) uses the correct method sort_values() with the parameters by='column_name' and ascending=False. This is the standard, modern Pandas syntax.
- Option (B) uses df.sort(), which is deprecated in modern Pandas versions, and the parameters order='desc' are incorrect.
- Option (C) uses df.order_by(), which is not a valid Pandas DataFrame function (it is SQL or Django ORM syntax).
- Option (D) uses df.sort_data(), which does not exist in Pandas.
Thus, option (A) is the only correct syntax.

Step 4: Final Answer:
The correct option is (A).