Sequence Types - Range
======================


.. toctree::
   :maxdepth: 1


Indices and tables
------------------

* :ref:`genindex`
* :ref:`modindex`
* :ref:`search`


.. _section_heading-Range:

Range
-----
**MUTABILITY:** Immutable

Creates an immutable sequence of integers. This class is commonly used to create a range of indexes to loop over. It can be used to fill other container types with content, if desired.

If you don't need to interact with the sequence, using a :py:class:`range` is cheaper then using a :py:class:`list` or :py:class:`tuple` as the :py:class:`range` object only stores the start, stop and step values (calculating individual items and sub-ranges on the fly as required).

Ranges can only be created using the :py:class:`range` constructor.

    .. py:function:: range(start=0, end=None, step=1),


Some examples:

* Create a sequence to represent the values 0 to 9:

   >>> foo = range(10)
   >>> foo
   range(10)

   In this case, ``foo`` points to the range *object*. Feed the :py:class:`range` object to the :py:class:`tuple` or :py:class:`list` constructor to see the actual values, as in:

   >>> list(foo)
   [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]


* Populate a list with values between 0 and 9, skipping every other one:

   >>> list(range(0, 10, 2))
   [0, 2, 4, 6, 8]

* Populate a list with values between -1 and -9, skipping every other one:

   >>> list(range(-1, -10, -2))
   [-1, -3, -5, -7, -9]


.. _section_heading-Range_Specific_Methods:

Range Specific Methods
^^^^^^^^^^^^^^^^^^^^^^^

There are no :py:class:`range` specific methods.

.. admonition:: Try it!
   :class: TryIt

   Try creating the following objects:

   * A list of the integers between 0 and 15.
   * A list of the integers between 5 and 20.
   * A list of every 5th integer between 5 and 20.