Creating a Categorical column
Back to the movie dataset from the streaming startup. Most rows in original_language use the same handful of codes (en, fr, es, …). Casting to Categorical encodes each unique label as an integer behind the scenes, saving memory on repeated strings.
This exercise is part of the course
Scaling and Optimizing Data Pipelines with Polars
Exercise instructions
- Cast the
original_languagecolumn topl.Categorical.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
movies_cat = movies.with_columns(
# Cast to Categorical to save memory
pl.col("original_language").____(pl.____)
)
result = movies_cat.select("movie_title", "original_language").head(8)
print(result)