.. _faqs:
Frequently asked questions
==========================
.. vale Google.FirstPerson = NO
What is PyAnsys?
----------------
PyAnsys is a set of open source technologies that let you interface with Ansys
CFX, Fluent, Mechanical APDL, System Coupling, and other Ansys products and
utilities using Python. You can use PyAnsys libraries in a Python environment of
your choice along with external Python libraries.
What is PyCFX?
--------------
PyCFX provides Python access to Ansys CFX. Its features let you seamlessly use
CFX in the Python ecosystem and provide broad access to native CFX features for performing
actions such as these:
- Launch CFX using a local Ansys installation.
- Connect to a CFX instance running on a remote machine.
PyCFX does not have a graphical user interface. You interact with PyCFX in the Python
environment of your choice, either interactively or using Python scripts.
Who uses PyCFX?
---------------
Engineers, product designers, consultants, and academia use PyCFX.
Which Python version should I use?
----------------------------------
PyCFX supports Python 3.10 through Python 3.14 on Windows and Linux.
You can use a suitable Python version from your Ansys installation. Python 3.10 ships with
Ansys 2023 R2 and later. For example, in a 2025 R2 Windows installation, the
executable file for Python 3.10 is typically located at:
``C:\Program Files\ANSYS Inc\v252\commonfiles\CPython\3_10\winx64\Release\python.exe``.
If you use Python from an Ansys installation, install PyCFX
in a Python virtual environment to prevent conflicts with
Ansys Python packages.
Alternatively, you can download any compatible Python version directly from
the `Python downloads `_ page. Run the
Python executable file as an administrator and select the
**Add Python [version] to PATH** checkbox on the first wizard page before
proceeding with the installation. On the last wizard page, which indicates that
Python is installed successfully, follow the instructions for disabling the path
length limit if you have long file paths.
Where can I find source code and documentation?
-----------------------------------------------
All PyAnsys public libraries are available on the `Ansys GitHub account
`_. The **Repositories** page displays the number of
repositories, which you can search by name. For example, to find all PyCFX
libraries, type ``pycfx`` in the search field.
The ``README.md`` file for the Ansys GitHub account lists the public PyAnsys
libraries. The links in this list lead to the repositories for the respective
libraries, where you can access their documentation. In addition to providing
general usage information, the documentation for a library includes practical
examples.
.. _faqs_cfxloc:
How does PyCFX find the location to launch CFX?
-----------------------------------------------
PyCFX locates installed Ansys versions based on environment variables in the form
``AWP_ROOT``, where ```` is a release number such as ``252`` for
Ansys 2025 R2. The corresponding environment variable is automatically configured on Windows
systems when you install a new Ansys release. On Linux systems, you must configure the
``AWP_ROOT`` environment variable to point to the absolute path of any
Ansys installation that you want to use with PyCFX. For example:
.. code-block:: console
set AWP_ROOT252=/apps/ansys_inc/v252
When PyCFX launches CFX, it determines which versions are available using these environment
variables. The Ansys version selected (if more than one is installed) is based on the following, in
decreasing order of precedence:
.. vale Google.Spacing = NO
#. The value of the ``product_version`` parameter passed to the function that launches a PyCFX
session, such as
:func:`from_install() `.
#. The latest supported installed version.
.. vale Google.Spacing = YES
How can I learn to use PyCFX?
-----------------------------
Depending on your preferences, you can use any or all of these methods to
learn how to use PyCFX:
- Review :ref:`ref_example_gallery`.
- Write scripts using capabilities such as these:
- IntelliSense to show available options for any given command. For example,
in `JupyterLab `_, press the tab key.
- Standard Python or PyAnsys tooling to print options related to a specified
object. For example, use the ``dir (