.. _install-mfix-linux:

Installing MFiX on Linux
------------------------

MFiX has been developed and tested on the following Linux distributions:

    - Ubuntu 22.04
    - Ubuntu 23.04
    - CentOS 7
    - CentOS 8

Other recent releases of Linux are also likely to work. If you have an issue running
or installing MFiX on your system, ask for help at :ref:`support-forum`.


Install Miniforge3
""""""""""""""""""

`Miniforge3` is a minimal version of the Anaconda Python distribution, which is used
for many scientific computing projects.  MFiX uses many supporting libraries, and the
easiest way to install MFiX and its dependencies is via the `conda` packages hosted at
`conda-forge` and NETL.  As of the 23.4 release we recommend the `Miniforge3`
installation over Anaconda for easier installation.  (However, you may continue to
use an existing Anaconda installation, see below.)  Note that the terms `conda package`
and `conda environment` refer generically to both Miniforge and Anaconda.

First, **download** the Linux x86_64 version of the `Miniforge3 installer <https://github.com/conda-forge/miniforge/releases/latest/download/Miniforge3-Linux-x86_64.sh>`__ (~33MB).  (There are also Miniforge installers for Linux on arm64 and ppc64 architectures, if you have such a system, see the `main Miniforge page <https://github.com/conda-forge/miniforge>`__.)

Next, go to your Downloads folder and **run** the downloaded file.

    #.  Open the Terminal application for your Linux desktop.
    #.  ``cd`` to the directory of the downloaded installer (for example ``~/Downloads``).
    #.  Run the downloaded installer: ``bash Miniforge3-Linux-x86_64.sh⏎``
    #.  When prompted for an installation location, hit enter to use the default, or enter the directory of your choice.
    #.  When prompted to run ``conda init``, say ``yes``.

Miniforge is now installed. In order for the changes to take effect, close the
terminal and open a new one. Verify that your ``PATH`` was updated by running
``conda`` in the new terminal.

If you are upgrading from a previous version of MFiX and you already have Miniforge or Anaconda installed, you may skip this step (but see note below).

.. note::


    If you have previously installed MFiX with Anaconda, you can continue to
    use your existing Anaconda installation.   We are recommending `Miniforge`
    for new installations.  If you are using Anaconda, we recommend setting
    channel priority to ``conda-forge``:

          .. code-block:: shell-session

             $ conda activate base
             (base)$ conda config --add channels conda-forge
             (base)$ conda config --set channel_priority strict


Install MFiX
""""""""""""

After installing Miniforge, install MFiX:

    #.  Open a terminal.
    #.  Browse to `MFiX Download <https://mfix.netl.doe.gov/mfix/download-mfix>`__ (requires registration and login)
    #.  Copy the installation command.
    #.  Paste it in the terminal.
    #.  Press enter to run the command.

  .. note:: If you have previously installed this version of MFiX, you will see the following message. Select ``y`` to confirm.  This will delete the previous MFiX installation and replace it.

          .. code-block:: shell-session

              WARNING: A conda environment already exists at ...
              Remove existing environment (y/[n])? y

MFiX will be installed in a new conda environment. The process may take a few
minutes to complete.

.. _activate-env-linux:

Run MFiX
""""""""

To run MFiX:

    #.  Open a terminal
    #.  Run |conda_act_inline|
    #.  Run ``mfix⏎`` to start MFiX

Your prompt should look something like this:

.. substitution-code-block:: shell-session

      $ conda create -n mfix-|release| mfix==|release| ...

      $ conda env list
      # conda environments:
      #
      base               *  /home/user/miniforge3
      mfix-|release|         /home/user/miniforge3/envs/mfix-|release|

      $ conda activate mfix-|release|

      (mfix-|release|)$ mfix

You are now ready to proceed to the :ref:`user-guide` and :ref:`tutorials`.

.. note::

    Activating a conda environment sets certain environment variables such as
    PATH in the current shell. It does not create a new shell session.

    You will need to activate the environment every time before running MFiX.


Deactivate conda environment
""""""""""""""""""""""""""""

After using MFiX you can just ``exit`` to leave the terminal session. However, if
you need to deactivate the |conda_env_inline| conda environment, you can do so with:

.. substitution-code-block:: shell-session

    (mfix-|release|)$ conda deactivate
    $

This returns to the base conda environment.

Uninstall MFiX
""""""""""""""

To remove an MFiX version, installed from conda packages, simply remove the conda
environment (if you have the environment activated, deactivate it first):

.. substitution-code-block:: shell-session

    (mfix-|release|)$ conda deactivate
    $ conda env remove -n mfix-|release|

To uninstall Miniforge entirely, remove the directory you installed it to. By default, this is ``~/miniforge3`` in your home directory. From the terminal:

.. code-block:: shell-session

    $ cd ~
    $ rm -rf miniforge3/



For Anaconda, the default directory is `anaconda3`.

Also be sure to edit your shell startup files to remove the `conda init` section at the end.


.. note::

    To learn more about managing conda environments, visit the `conda documentation
    <https://conda.io/projects/conda/en/latest/user-guide/tasks/manage-environments.html>`__ .
    To learn more about miniforge, see the `Miniforge3 README <https://github.com/conda-forge/miniforge>`__.