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Column· method

Column.is_null

a bool column, true where the value is null

Python

is_null() -> Column

Returns Column — a boolean Column, true where the value is null

Example#

Python

t.filter(t["score"].is_null())      # keep only the rows missing a score

Notes#

Immediately computes a boolean Column (a mask) you pass to filter. It does not build a deferred expression. It is the exact complement of is_valid. For a per-column count of nulls across the whole table, use Table.null_report.

See also#

API: is_valid · Table.filter · Table.null_report

Guides: Tables & data flow · Clean a CSV

By LSD Team · Last updated Sep 09, 2026 Ask a question View as Markdown