DOLFINx is the computational environment of FEniCSx and implements the FEniCS Problem Solving Environment in C++ and Python.

DOLFINx is a new version of DOLFIN and is being actively developed.

Documentation can be viewed at:

• https://docs.fenicsproject.org/dolfinx/main/cpp/
• https://docs.fenicsproject.org/dolfinx/main/python/

To build and install the C++ core, in the cpp/ directory, run::

mkdir build
cd build
cmake ..
make install

To install the Python interface, first install the C++ core, and then in the python/ directory run::

pip install .

(you may need to use pip3, depending on your system).

For detailed instructions, see https://docs.fenicsproject.org/dolfinx/main/python/installation.

Spack automates the installation from source and is recommended for building DOLFINx on HPC systems. To build the most recent release using Spack (assuming a bash-compatible shell):

git clone https://github.com/spack/spack.git
. ./spack/share/spack/setup-env.sh
spack env create fenicsx-env
spack env activate fenicsx-env
spack add py-fenics-dolfinx cflags="-O3" fflags="-O3"
spack install

See the Spack documentation for comprehensive instructions.

Recommendations

• macOS: conda.
• Linux: apt (Ubuntu/Debian), docker or conda. See also Spack.
• Windows: docker, or install WSL2 and use Ubuntu.

To install the latest stable release of the Python interface, with pyvista support for visualisation, using conda:

conda create -n fenicsx-env
conda activate fenicsx-env
conda install -c conda-forge fenics-dolfinx mpich pyvista

conda is distributed with Anaconda and Miniconda. The conda recipe is hosted on conda-forge.

Name	Downloads	Version	Platforms

Note Windows packages are not available. This is due to some DOLFINx dependencies not supporting Windows.

The Ubuntu PPA contains binary packages of the FEniCSx components. To install:

add-apt-repository ppa:fenics-packages/fenics
apt update
apt install fenicsx

When a version of DOLFINx is released we aim to provide a build for the latest stable version of Ubuntu. All other versions are provided on a best-effort basis.

DOLFINx is included with various versions of Debian. Install with apt-get install fenicsx.

A Docker image with the latest stable release of DOLFINx:

docker run -ti dolfinx/dolfinx:stable

To switch between real and complex builds of DOLFINx/PETSc.

source /usr/local/bin/dolfinx-complex-mode
source /usr/local/bin/dolfinx-real-mode

A Jupyter Lab environment with the latest stable release of DOLFINx:

docker run --init -ti -p 8888:8888 dolfinx/lab:stable  # Access at http://localhost:8888

A Docker image with DOLFINx built nightly:

docker run -ti dolfinx/dolfinx:nightly

A development image with all of the dependencies required to build the latest stable release of the FEniCSx components:

docker run -ti dolfinx/dev-env:stable

A development image with all of the dependencies required to build the main branch of the FEniCSx components:

docker run -ti dolfinx/dev-env:current

All Docker images support arm64 and amd64 architectures.

For a full list of tags, including versioned images, see https://hub.docker.com/u/dolfinx

Information about how to contribute to DOLFINx can be found here.

DOLFINx is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

DOLFINx is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with DOLFINx. If not, see http://www.gnu.org/licenses/.

For questions about using DOLFINx, visit the FEniCS Discourse page:

https://fenicsproject.discourse.group/

or use the FEniCS Slack channel:

https://fenicsproject.slack.com/

(use https://join.slack.com/t/fenicsproject/shared_invite/zt-1lraknsp1-6_3Js5kueDIyWgF192d3nA to sign up)

For bug reports visit:

https://github.com/FEniCS/dolfinx