ChemApp for Python with Python virtualenv
*****************************************

The following procedures were written for Windows and Linux users that prefer
using Python virtual environments without the use of an :term:`IDE`.


Windows
~~~~~~~
#. Download Python and Pip.

   Download and install Python as explained in the "ChemApp for Python with a
   Bare Python Installation" section. Also complete the "Additional
   installations" mentioned in this section to install "pip" and "setuptools".

#. Make a virtual environment.

   A step-by-step guide on creating a virtual environment can be found
   `here <https://packaging.python.org/guides/installing-using-pip-and-virtualenv/>`_.
   In this example, we will name our virtual environment "chemapp-light".

#. Download ChemApp for Python's free Light edition.

   Download and install ChemApp for Python Light as explained in the "Installing
   ChemApp for Python on Bare Python" section. In this example, ChemApp for
   Python was downloaded to

   .. code-block:: bat

      C:\Python\Scripts\python-packages\

#. Install ChemApp for Python in a virtual environment.

   Activate the newly created virtual environment with the following command:

   .. code-block:: bat

      .\chemapp-light\Scripts\activate

   ChemApp for Python can now be installed using

   .. code-block:: bat

      pip install C:\Python\Scripts\python-packages\``chemapp831.2.0-win-chemapp8.3.1-python3.12.7.tar.gz``'

   ``pip list`` can be used to ensure that the ``chemapp`` package was
   successfully installed.


Linux
~~~~~
The procedure for installing ChemApp for Python on Linux using a Python virtual
environment is as follows:

#. Install ``virtualenv``.

   In the terminal, run the following installation command:

   .. code-block:: bat

      pip install virtualenv

#. Add a new virtual environment.

   Once the ``virtualenv`` installtion is completed it is required to create a
   virtual environment. The name of the virtual environment is determined by the
   user, for simplicity, ``my-chemapp-env`` is used to name the environment.
   The environment can be created in any directory with its specific
   ``file_path``.

   .. code-block:: bat

      virtualenv file_path/my-chemapp-env

   It is not necessary to add a ``file_path``, then by default, the virtual
   environment will be created in the ``/home`` directory.

#. Activate the virtual environment.

   To activate the virtual environment run the following command in the
   terminal.

   .. code-block:: bat

      source file_path/my-chemapp-env/bin/activate

   Once the virtual environment is active, the name of the virtual environment
   will be displayed in closed brackets on the left-hand side of the terminal
   command line, e.g. ``(my-chemapp-env)``.  To deactivate the environment
   simply run ``deactivate`` in the terminal command line.

#. Install the Python version.

   To install the correct Python version type the following command in the
   terminal with the virtual environment active:

   .. code-block:: bat

      virtualenv --download python3.9.1

#. Install ChemApp for Python.

   ChemApp for Python Light can be downloaded from the GTT Technologies website
   for the Linux version. You will need to ``cd file_path`` to the directory
   where the ChemApp for Python distribution package is stored. Install the
   ChemApp for Python package with the following command in the terminal:

   .. code-block:: bat

      pip install ``chemapp831.2.0-linux-chemapp8.3.1-python3.12.7.tar.gz``