Filter data with any in polars

contains_any

You’re a teacher who has just finished grading student exams, and you want to identify the students who either got a C or a D so that you can talk to them about their poor performance. Below is a dataframe showing student grades.

shape: (4, 2)

Pupil	Grade
str	str
"Lauren"	"A+"
"Larry"	"B"
"Chanda"	"B+"
"Katis"	"C"

Filter data

To display the students who either got a C or a D, you use the Polars expression contains_any like this:

(df
 .filter(pl.col('Grade').str.contains_any(['C','D']))
 )

shape: (1, 2)

Pupil	Grade
str	str
"Katis"	"C"

Only one student matched the filter condition.

Note

The code worked even though there was no D grade. That’s the power of contains_any. It works whether one or both of the specified values are present.

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