cudf.CategoricalDtype

class cudf.CategoricalDtype(categories=None, ordered: bool = False)

Type for categorical data with the categories and orderedness.

Parameters

categoriessequence, optional

Must be unique, and must not contain any nulls. The categories are stored in an Index, and if an index is provided the dtype of that index will be used.

orderedbool or None, default False

Whether or not this categorical is treated as a ordered categorical. None can be used to maintain the ordered value of existing categoricals when used in operations that combine categoricals, e.g. astype, and will resolve to False if there is no existing ordered to maintain.

Examples

>>> import cudf
>>> dtype = cudf.CategoricalDtype(categories=['b', 'a'], ordered=True)
>>> cudf.Series(['a', 'b', 'a', 'c'], dtype=dtype)
0       a
1       b
2       a
3    <NA>
dtype: category
Categories (2, object): ['b' < 'a']

Attributes

categories	An Index containing the unique categories allowed.
ordered	Whether the categories have an ordered relationship.

Methods

from_pandas(dtype)	Convert a pandas.CategrocialDtype to cudf.CategoricalDtype
to_pandas()	Convert a cudf.CategoricalDtype to pandas.CategoricalDtype

property categories: GenericIndex

An Index containing the unique categories allowed.

Examples

>>> import cudf
>>> dtype = cudf.CategoricalDtype(categories=['b', 'a'], ordered=True)
>>> dtype.categories
StringIndex(['b' 'a'], dtype='object')

classmethod from_pandas(dtype: CategoricalDtype) → CategoricalDtype

Convert a pandas.CategrocialDtype to cudf.CategoricalDtype

Examples

>>> import cudf
>>> import pandas as pd
>>> pd_dtype = pd.CategoricalDtype(categories=['b', 'a'], ordered=True)
>>> pd_dtype
CategoricalDtype(categories=['b', 'a'], ordered=True)
>>> cudf_dtype = cudf.CategoricalDtype.from_pandas(pd_dtype)
>>> cudf_dtype
CategoricalDtype(categories=['b', 'a'], ordered=True)

property ordered: bool

Whether the categories have an ordered relationship.

to_pandas() → CategoricalDtype

Convert a cudf.CategoricalDtype to pandas.CategoricalDtype

Examples

>>> import cudf
>>> dtype = cudf.CategoricalDtype(categories=['b', 'a'], ordered=True)
>>> dtype
CategoricalDtype(categories=['b', 'a'], ordered=True)
>>> dtype.to_pandas()
CategoricalDtype(categories=['b', 'a'], ordered=True)