:orphan:

.. include:: ../links.inc

.. _install-python:

Installing Python
^^^^^^^^^^^^^^^^^

AVNI requires Python and several Python packages. AVNI version |version|
requires Python version |min_python_version| or higher. We recommend the
`Anaconda`_ distribution of Python, which comes with more than 250 scientific
packages pre-bundled and includes the ``conda`` command line tool for installing
new packages and managing different package sets ("environments") for different
projects.

To get started, follow the `installation instructions for Anaconda`_. When you
are done, if you type the following commands in a command shell, you should see
outputs similar to the following (assuming you installed conda to
``/home/user/anaconda3``):


.. tab-set::
    :class: platform-selector-tabset

    .. tab-item:: Linux
        :name: linux-manual-install

        .. code-block:: console

            $ conda --version && python --version conda 4.9.2 Python 3.7.7 ::
            Anaconda, Inc. $ which python /home/user/anaconda3/bin/python $
            which pip /home/user/anaconda3/bin/pip


    .. tab-item:: macOS
        :name: macos-manual-install

        .. code-block:: console

            $ conda --version && python --version conda 4.9.2 Python 3.7.7 $
            which python /Users/user/opt/anaconda3/bin/python $ which pip
            /Users/user/opt/anaconda3/bin/pip


    .. tab-item:: Windows
        :name: windows-manual-install

        Most of our instructions start with ``$``, which indicates that the
        commands are designed to be run from a ``bash`` command shell.

        Windows command prompts do not expose the same command-line tools as
        ``bash`` shells, so commands like ``which`` will not work. You can test
        your installation in Windows ``cmd.exe`` shells with ``where`` instead:

        .. code-block:: doscon

            > where python C:\Users\user\anaconda3\python.exe > where pip
            C:\Users\user\anaconda3\Scripts\pip.exe


.. raw:: html

    <div width="100%" height="0 px" style="margin: 0 0 15px;"></div>


.. dropdown:: If you get an error...
    :color: danger
    :icon: alert-fill

    .. rubric:: If you see something like:

    ::

        conda: command not found

    It means that your ``PATH`` variable (what the system uses to find programs)
    is not set properly. In a correct installation, doing::

        $ echo $PATH
        ...:/home/user/anaconda3/bin:...

    Will show the Anaconda binary path (above) somewhere in the output (probably
    at or near the beginning), but the ``command not found`` error suggests that
    it is missing.

    On Linux or macOS, the installer should have put something like the
    following in your ``~/.bashrc`` or ``~/.bash_profile`` (or your
    ``.zprofile`` if you're using macOS Catalina or later, where the default
    shell is ``zsh``):

    .. code-block:: console

        # >>> conda initialize >>> # !! Contents within this block are managed
        by 'conda init' !! __conda_setup= ... ... # <<< conda initialize <<<

    If this is missing, it is possible that you are not on the same shell that
    was used during the installation. You can verify which shell you are on by
    using the command::

        $ echo $SHELL

    If you do not find this line in the configuration file for the shell you are
    using (bash, zsh, tcsh, etc.), try running::

        conda init

    in your command shell. If your shell is not ``cmd.exe`` (Windows) or
    ``bash`` (Linux, macOS) you will need to pass the name of the shell to the
    ``conda init`` command. See ``conda init --help`` for more info and
    supported shells.

    You can also consult the Anaconda documentation and search for Anaconda
    install tips (`Stack Overflow`_ results are often helpful) to fix these or
    other problems when ``conda`` does not work.


.. raw:: html

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