path: root/docs/formats.rst

.. _formats:

=======
Formats
=======

Tablib supports a wide variety of different tabular formats, both for input and
output. Moreover, you can :ref:`register your own formats <newformats>`.

cli
===

The ``cli`` format is currently export-only. The exports produce a representation
table suited to a terminal.

When exporting to a CLI you can pass the table format  with the ``tablefmt``
parameter, the supported formats are::

    >>> import tabulate
    >>> list(tabulate._table_formats)
    ['simple', 'plain', 'grid', 'fancy_grid', 'github', 'pipe', 'orgtbl',
     'jira', 'presto', 'psql', 'rst', 'mediawiki', 'moinmoin', 'youtrack',
     'html', 'latex', 'latex_raw', 'latex_booktabs', 'tsv', 'textile']

For example::

    dataset.export("cli", tablefmt="github")
    dataset.export("cli", tablefmt="grid")

This format is optional, install Tablib with ``pip install "tablib[cli]"`` to
make the format available.

csv
===

When you import CSV data, you can specify if the first line of your data source
is headers with the ``headers`` boolean parameter (defaults to ``True``)::

    import tablib

    tablib.import_set(your_data_stream, format='csv', headers=False)

When exporting with the ``csv`` format, the top row will contain headers, if
they have been set. Otherwise, the top row will contain the first row of the
dataset.

When importing a CSV data source or exporting a dataset as CSV, you can pass any
parameter supported by the :py:func:`csv.reader` and :py:func:`csv.writer`
functions. For example::

    tablib.import_set(your_data_stream, format='csv', dialect='unix')

    dataset.export('csv', delimiter=' ', quotechar='|')

.. admonition:: Line endings

     Exporting uses \\r\\n line endings by default so, make sure to include
     ``newline=''`` otherwise you will get a blank line between each row
     when you open the file in Excel::

         with open('output.csv', 'w', newline='') as f:
             f.write(dataset.export('csv'))

     If you do not do this, and you export the file on Windows, your
     CSV file will open in Excel with a blank line between each row.

dbf
===

Import/export using the dBASE_ format.

.. admonition:: Binary Warning

    The ``dbf`` format contains binary data, so make sure to write in binary
    mode::

        with open('output.dbf', 'wb') as f:
            f.write(dataset.export('dbf')

.. _dBASE: https://en.wikipedia.org/wiki/DBase

df (DataFrame)
==============

Import/export using the pandas_ DataFrame format. This format is optional,
install Tablib with ``pip install "tablib[pandas]"`` to make the format available.

.. _pandas: https://pandas.pydata.org/

html
====

The ``html`` format is currently export-only. The exports produce an HTML page
with the data in a ``<table>``. If headers have been set, they will be used as
table headers.

This format is optional, install Tablib with ``pip install "tablib[html]"`` to
make the format available.

jira
====

The ``jira`` format is currently export-only. Exports format the dataset
according to the Jira table syntax::

    ||heading 1||heading 2||heading 3||
    |col A1|col A2|col A3|
    |col B1|col B2|col B3|

json
====

Import/export using the JSON_ format. If headers have been set, a JSON list of
objects will be returned. If no headers have been set, a JSON list of lists
(rows) will be returned instead.

Import assumes (for now) that headers exist.

.. _JSON: http://json.org/

latex
=====

Import/export using the LaTeX_ format. This format is export-only.
If a title has been set, it will be exported as the table caption.

.. _LaTeX: https://www.latex-project.org/

ods
===

Export data in OpenDocument Spreadsheet format. The ``ods`` format is currently
export-only.

This format is optional, install Tablib with ``pip install "tablib[ods]"`` to
make the format available.

.. admonition:: Binary Warning

    :class:`Dataset.ods` contains binary data, so make sure to write in binary mode::

        with open('output.ods', 'wb') as f:
            f.write(data.ods)

rst
===

Export data as a reStructuredText_ table representation of a dataset. The
``rst`` format is export-only.

Exporting returns a simple table if the text in the first column is never
wrapped, otherwise returns a grid table::

    >>> from tablib import Dataset
    >>> bits = ((0, 0), (1, 0), (0, 1), (1, 1))
    >>> data = Dataset()
    >>> data.headers = ['A', 'B', 'A and B']
    >>> for a, b in bits:
    ...     data.append([bool(a), bool(b), bool(a * b)])
    >>> table = data.export('rst')
    >>> table.split('\\n') == [
    ...     '=====  =====  =====',
    ...     '  A      B    A and',
    ...     '                B  ',
    ...     '=====  =====  =====',
    ...     'False  False  False',
    ...     'True   False  False',
    ...     'False  True   False',
    ...     'True   True   True ',
    ...     '=====  =====  =====',
    ... ]
    True

.. _reStructuredText: http://docutils.sourceforge.net/rst.html

tsv
===

A variant of the csv_ format with tabulators as fields separators.

xls
===

Import/export data in Legacy Excel Spreadsheet representation.

This format is optional, install Tablib with ``pip install "tablib[xls]"`` to
make the format available.

.. note::

    XLS files are limited to a maximum of 65,000 rows. Use xlsx_ to avoid this
    limitation.

.. admonition:: Binary Warning

    The ``xls`` file format is binary, so make sure to write in binary mode::

        with open('output.xls', 'wb') as f:
            f.write(data.export('xls'))

xlsx
====

Import/export data in Excel 07+ Spreadsheet representation.

This format is optional, install Tablib with ``pip install "tablib[xlsx]"`` to
make the format available.

The ``import_set()`` and ``import_book()`` methods accept keyword
argument ``read_only``.  If its value is ``True`` (the default), the
XLSX data source is read lazily.  Lazy reading generally reduces time
and memory consumption, especially for large spreadsheets.  However,
it relies on the XLSX data source declaring correct dimensions.  Some
programs generate XLSX files with incorrect dimensions.  Such files
may need to be loaded with this optimization turned off by passing
``read_only=False``.

.. note::

    When reading an ``xlsx`` file containing formulas in its cells, Tablib will
    read the cell values, not the cell formulas.

.. versionchanged:: 2.0.0

    Reads cell values instead of formulas.

.. admonition:: Binary Warning

    The ``xlsx`` file format is binary, so make sure to write in binary mode::

        with open('output.xlsx', 'wb') as f:
            f.write(data.export('xlsx'))

yaml
====

Import/export data in the YAML_ format.
When exporting, if headers have been set, a YAML list of objects will be
returned. If no headers have been set, a YAML list of lists (rows) will be
returned instead.

Import assumes (for now) that headers exist.

This format is optional, install Tablib with ``pip install "tablib[yaml]"`` to
make the format available.

.. _YAML: https://yaml.org