cudf.ListDtype#

class cudf.ListDtype(element_type: Any)#

Type to represent list data.

Parameters

element_typeobject: A dtype with which represents the element types in the list.

Examples

>>> import cudf
>>> list_dtype = cudf.ListDtype("int32")
>>> list_dtype
ListDtype(int32)

A nested list dtype can be created by:

>>> nested_list_dtype = cudf.ListDtype(list_dtype)
>>> nested_list_dtype
ListDtype(ListDtype(int32))

Attributes

element_type

Returns the element type of the ListDtype. Returns ——- Dtype Examples ——– >>> import cudf >>> deep_nested_type = cudf.ListDtype(cudf.ListDtype(cudf.ListDtype(“float32”))) >>> deep_nested_type ListDtype(ListDtype(ListDtype(float32))) >>> deep_nested_type.element_type ListDtype(ListDtype(float32)) >>> deep_nested_type.element_type.element_type ListDtype(float32) >>> deep_nested_type.element_type.element_type.element_type ‘float32’

leaf_type

Returns the type of the leaf values. Examples ——– >>> import cudf >>> deep_nested_type = cudf.ListDtype(cudf.ListDtype(cudf.ListDtype(“float32”))) >>> deep_nested_type ListDtype(ListDtype(ListDtype(float32))) >>> deep_nested_type.leaf_type ‘float32’

Methods

`from_arrow`(typ)	Creates a `ListDtype` from `pyarrow.ListType`.
`to_arrow`()	Convert to a `pyarrow.ListType`

property element_type: Union[ExtensionDtype, str, dtype]#

Returns the element type of the ListDtype.

Returns

Dtype

Examples

>>> import cudf
>>> deep_nested_type = cudf.ListDtype(cudf.ListDtype(cudf.ListDtype("float32")))
>>> deep_nested_type
ListDtype(ListDtype(ListDtype(float32)))
>>> deep_nested_type.element_type
ListDtype(ListDtype(float32))
>>> deep_nested_type.element_type.element_type
ListDtype(float32)
>>> deep_nested_type.element_type.element_type.element_type
'float32'

classmethod from_arrow(typ)#

Creates a ListDtype from pyarrow.ListType.

Parameters

typpyarrow.ListType: A pyarrow.ListType that has to be converted to ListDtype.

Returns

objListDtype

Examples

>>> import cudf
>>> import pyarrow as pa
>>> arrow_type = pa.infer_type([[1]])
>>> arrow_type
ListType(list<item: int64>)
>>> list_dtype = cudf.ListDtype.from_arrow(arrow_type)
>>> list_dtype
ListDtype(int64)

property leaf_type#

Returns the type of the leaf values.

Examples

>>> import cudf
>>> deep_nested_type = cudf.ListDtype(cudf.ListDtype(cudf.ListDtype("float32")))
>>> deep_nested_type
ListDtype(ListDtype(ListDtype(float32)))
>>> deep_nested_type.leaf_type
'float32'

to_arrow()#

Convert to a pyarrow.ListType

Examples

>>> import cudf
>>> list_dtype = cudf.ListDtype(cudf.ListDtype("float32"))
>>> list_dtype
ListDtype(ListDtype(float32))
>>> list_dtype.to_arrow()
ListType(list<item: list<item: float>>)