Using a categorical expression
The team wants a quick flag for movies whose original_language code starts with e (English, Estonian, …). Polars' categorical namespace has its own string-like expressions that work directly on the encoded column, no cast back to String needed.
movies_cat is available with original_language already cast to pl.Categorical.
Questo esercizio fa parte del corso
Scaling and Optimizing Data Pipelines with Polars
Istruzioni dell'esercizio
- Use the categorical namespace to check whether
original_languagestarts with"e". - Alias the new boolean column as
starts_with_e.
esercizio interattivo pratico
Prova questo esercizio completando questo codice di esempio.
result = movies_cat.select(
"movie_title",
"original_language",
# Flag categorical values starting with "e"
pl.col("original_language").____.starts_with("____").alias("____"),
).head(8)
print(result)