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Docs/ API Reference/ Column/ is_valid
Column· method

Column.is_valid

a bool column, true where the value is present (not null)

Python
is_valid() -> Column

Returns Column — a boolean Column, true where the value is not null

Example#

Python
t.filter(t["name"].is_valid())      # drop rows whose name is null

Combine it with other conditions:

Python
t.filter((t["score"] > 10) & t["name"].is_valid())

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_null.

See also#

API: is_null · Table.filter · Column

Guides: Tables & data flow · Clean a CSV

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