polars.LazyFrame.collect_schema

LazyFrame.collect_schema() → Schema

解析此LazyFrame的模式。

示例

确定模式。

>>> lf = pl.LazyFrame(
...     {
...         "foo": [1, 2, 3],
...         "bar": [6.0, 7.0, 8.0],
...         "ham": ["a", "b", "c"],
...     }
... )
>>> lf.collect_schema()
Schema({'foo': Int64, 'bar': Float64, 'ham': String})

访问模式的各种属性。

>>> schema = lf.collect_schema()
>>> schema["bar"]
Float64
>>> schema.names()
['foo', 'bar', 'ham']
>>> schema.dtypes()
[Int64, Float64, String]
>>> schema.len()
3