.. currentmodule:: torcharrow

torcharrow.Column
==========================

A :class:`torcharrow.Column` is a 1-dimension torch.Tensor like data structure containing
elements of a single data type. It also supports non-numeric types such as string,
list, struct.

Data types
----------

TorchArrow defines the following data types for column, which is in module ``torcharrow.dtypes``
(abbreviated as ``dt`` in table below):

======================================= ===========================================
Data type                               dtype
======================================= ===========================================
32-bit floating point                   ``dt.float32`` or ``dt.Float32(nullable)``
64-bit floating point                   ``dt.float64`` or ``dt.Float64(nullable)``
8-bit signed integer                    ``dt.int8`` or ``dt.Int8(nullable)``
16-bit signed integer                   ``dt.int16`` or ``dt.Int16(nullable)``
32-bit signed integer                   ``dt.int32`` or ``dt.Int32(nullable)``
64-bit signed integer                   ``dt.int64`` or ``dt.Int64(nullable)``
Boolean                                 ``dt.boolean`` or ``dt.Boolean(nullable)``
String                                  ``dt.string`` or ``dt.String(nullable)``
List                                    ``dt.List(item_dtype, nullable)``
Struct                                  ``dt.Struct(fields, nullable)``
======================================= ===========================================

Column class reference
------------------------------
.. class:: Column()

.. autoattribute:: Column.dtype
.. autoattribute:: Column.device
.. autoattribute:: Column.length
.. autoattribute:: Column.null_count

.. autosummary::
    :toctree: generated
    :nosignatures:
    :template: class.rst

    Column.head
    Column.tail
    Column.cast
    Column.is_valid_at
    Column.append
    Column.isin

    Column.all
    Column.any

    Column.map
    Column.filter
    Column.flatmap
    Column.transform

    Column.fill_null
    Column.drop_null
    Column.drop_duplicates

    Column.to_arrow
    Column.to_tensor
    Column.to_pylist
    Column.to_pandas


NumericalColumn class reference
-----------------------------------
.. class:: NumericalColumn()

.. autosummary::
    :toctree: generated
    :nosignatures:
    :template: class.rst

    NumericalColumn.abs
    NumericalColumn.ceil
    NumericalColumn.floor
    NumericalColumn.round
    NumericalColumn.log

    NumericalColumn.describe
    NumericalColumn.min
    NumericalColumn.max
    NumericalColumn.sum
    NumericalColumn.mean
    NumericalColumn.std
    NumericalColumn.median


StringColumn class reference
-----------------------------------
.. class:: StringColumn()

.. autosummary::
    :toctree: generated
    :nosignatures:
    :template: class.rst

    istring_column.StringMethods.length
    istring_column.StringMethods.slice
    istring_column.StringMethods.split
    istring_column.StringMethods.strip

    istring_column.StringMethods.isalpha
    istring_column.StringMethods.isnumeric
    istring_column.StringMethods.isalnum
    istring_column.StringMethods.isdigit
    istring_column.StringMethods.isdecimal
    istring_column.StringMethods.isspace
    istring_column.StringMethods.islower
    istring_column.StringMethods.isupper
    istring_column.StringMethods.istitle

    istring_column.StringMethods.lower
    istring_column.StringMethods.upper

    istring_column.StringMethods.startswith
    istring_column.StringMethods.endswith
    istring_column.StringMethods.count
    istring_column.StringMethods.find
    istring_column.StringMethods.replace
    istring_column.StringMethods.match
    istring_column.StringMethods.contains
    istring_column.StringMethods.findall

ListColumn class reference
-----------------------------------
.. class:: ListColumn()

.. autosummary::
    :toctree: generated
    :nosignatures:
    :template: class.rst

    ilist_column.ListMethods.length
    ilist_column.ListMethods.slice
    ilist_column.ListMethods.vmap