Method dtype

python/pyarrow/interchange/column.py:265–294

Dtype description as a tuple ``(kind, bit-width, format string, endianness)``. Bit-width : the number of bits as an integer Format string : data type description format string in Apache Arrow C Data Interface format. Endianness : curr

(self)

    @property
    def dtype(self) -> Tuple[DtypeKind, int, str, str]:
        """
        Dtype description as a tuple ``(kind, bit-width, format string,
        endianness)``.

        Bit-width : the number of bits as an integer
        Format string : data type description format string in Apache Arrow C
                        Data Interface format.
        Endianness : current only native endianness (``=``) is supported

        Notes:
            - Kind specifiers are aligned with DLPack where possible (hence the
              jump to 20, leave enough room for future extension)
            - Masks must be specified as boolean with either bit width 1 (for
              bit masks) or 8 (for byte masks).
            - Dtype width in bits was preferred over bytes
            - Endianness isn't too useful, but included now in case in the
              future we need to support non-native endianness
            - Went with Apache Arrow format strings over NumPy format strings
              because they're more complete from a dataframe perspective
            - Format strings are mostly useful for datetime specification, and
              for categoricals.
            - For categoricals, the format string describes the type of the
              categorical in the data buffer. In case of a separate encoding of
              the categorical (e.g. an integer to string mapping), this can
              be derived from ``self.describe_categorical``.
            - Data types not included: complex, Arrow-style null, binary,
              decimal, and nested (list, struct, map, union) dtypes.
        """
        return self._dtype

    def _dtype_from_arrowdtype(
        self, dtype: pa.DataType, bit_width: int