Instruction: Illustrate with an example how you would update a DataFrame's column values based on logical conditions involving other columns.
Context: This question assesses the candidate's ability to perform complex, condition-based data manipulations within a DataFrame, a critical skill for data analysis and transformation tasks.
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Let's imagine we have a DataFrame named df that includes sales data. The columns are Year, Month, Product, and Sales, where Sales represents the number of units sold. Our goal is to introduce a new column, SalesCategory, which categorizes sales into Low, Medium, and High based on the number of units sold. The conditions are as follows: sales below 50 are categorized as Low, sales between 50 and 100 are Medium, and sales above 100 are High.
First, we need to clarify our approach. We will use the np.select() method from the NumPy library to evaluate multiple conditions and assign values...