polars.DataFrame.write_ndjson#

DataFrame.write_ndjson(file: IOBase | str | Path | None = None) → str | None[source]#

Serialize to newline delimited JSON representation.

Parameters:

file: File path or writable file-like object to which the result will be written. If set to None (default), the output is returned as a string instead.

Examples

>>> df = pl.DataFrame(
...     {
...         "foo": [1, 2, 3],
...         "bar": [6, 7, 8],
...     }
... )
>>> df.write_ndjson()
'{"foo":1,"bar":6}\n{"foo":2,"bar":7}\n{"foo":3,"bar":8}\n'