Installation¶

This page builds build/simple.x, the library libsimple and optionally the Python package pysimple from source. Run all commands from the repository root.

Prerequisites¶

CMake ≥ 3.22, Ninja, GNU Fortran, Git, NetCDF-C and NetCDF-Fortran, LAPACK and BLAS (OpenBLAS for setup-venv.sh), and Python ≥ 3.10 with venv for pysimple and the tools in tools/.

# Arch Linux
sudo pacman -S gcc-fortran cmake ninja netcdf netcdf-fortran lapack openblas

# Ubuntu or Debian
sudo apt install gfortran cmake ninja-build libnetcdf-dev libnetcdff-dev \
    liblapack-dev libopenblas-dev python3-venv

# macOS with Homebrew
brew install gcc cmake ninja netcdf netcdf-fortran lapack openblas

On macOS, select the Homebrew GNU compilers before the first configuration; Apple Clang has no OpenMP:

export FC=gfortran
export CC="gcc-$(gfortran -dumpversion | cut -d. -f1)"
export CXX="g++-$(gfortran -dumpversion | cut -d. -f1)"
export CPATH="$(brew --prefix)/include${CPATH:+:$CPATH}"
export LIBRARY_PATH="$(brew --prefix)/lib${LIBRARY_PATH:+:$LIBRARY_PATH}"

The first configuration downloads, with CMake FetchContent and therefore with network access to GitHub, libneo (fields, splines, coordinates, chartmaps), fortnum (root finders, ODE integrators), fortio (file I/O, through libneo) and fortplot. Pinned revisions are in cmake/dependency_versions.json.

Build¶

git clone https://github.com/itpplasma/SIMPLE.git
cd SIMPLE
make                 # Release build in build/
make CONFIG=Fast     # native CPU flags; use for production runs

make runs cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release and cmake --build build. Further options:

Option	Default	Effect
`CMAKE_BUILD_TYPE`	`Release`	`Release`, `Fast` (native CPU flags), `Debug` or `Profile`
`ENABLE_OPENMP`	`ON`	OpenMP over particles
`ENABLE_PYTHON_INTERFACE`	`ON`	`pysimple` bindings (needs numpy, f90wrap)
`SIMPLE_ENABLE_CGAL`	`OFF`	STL walls with CGAL (downloads CGAL, needs Boost headers); Wall heat loads
`SIMPLE_ENABLE_CUDA`	`OFF`	native CUDA tracing; GPU tracing
`SIMPLE_DETERMINISTIC_FP`	`OFF`	no fast-math, bitwise reproducible (`make build-deterministic`)
`LIBNEO_REF`	automatic	libneo branch, tag or commit (`make LIBNEO_REF=...`)
`LIBNEO_SOURCE_DIR`	unset	local libneo checkout (`make LIBNEO_PATH=...`)

Builds with different options live in separate build directories, for example with CGAL:

cmake -S . -B build-cgal -G Ninja -DCMAKE_BUILD_TYPE=Release \
    -DSIMPLE_ENABLE_CGAL=ON
cmake --build build-cgal --target simple.x

Python package¶

setup-venv.sh creates .venv in the repository, installs the Python requirements, builds SIMPLE and installs pysimple in editable mode:

./setup-venv.sh
source .venv/bin/activate
python -c "import pysimple"

In an existing environment, run python -m pip install -r requirements.txt and python -m pip install --no-build-isolation -e .; pip builds the Fortran code with scikit-build-core in _skbuild/ (several minutes). python -m pip install '.[plotting]' adds Matplotlib and netCDF4 for Plotting results.

Check¶

make test-fast

builds with SIMPLE_DETERMINISTIC_FP=ON and runs all tests except those labelled slow, regression, performance and scalability. Next: Quick start.