[Note: this project is in active development.]

This is a repository of SUNDIALS-based applications to assess and demonstrate the parallel performance of new capabilities that have been added to SUNDIALS as part of the FRONTIERS SciDAC project.

The following steps describe how to build the demonstration code in a Linux or MacOS environment.

To obtain the code, clone this repository with Git:

  git clone https://github.com/sundials-codes/frontiers-demonstrations.git

To compile the codes in this repository you will need:

• CMake 3.20 or newer (both for SUNDIALS and for this repository)

• C compiler (C99 standard) and C++ compiler (C++11 standard)

• an MPI library e.g., OpenMPI, MPICH, etc.

The codes in this repository depend on one external library:

• SUNDIALS

If this is not already available on your system, it may be cloned from GitHub as a submodule. After cloning this repository using the command above, you can retrieve this submodule via:

  cd frontiers-demonstrations/deps
  git submodule init
  git submodule update

We note that a particular benefit of retrieving dependencies using submodules is that they point to specific revisions of dependent libraries that are known to work correctly with the codes in this repository.

Additionally, the python postprocessing scripts in this repository require a number of additional python packages, including NumPy, Matplotlib, and Pandas.

We recommend that users follow the posted instructions for installing SUNDIALS.

The SUNDIALS build instructions are linked here. Note that of the many SUNDIALS build options, this repository requires only a minimal SUNDIALS build with MPI. The following steps can be used to build SUNDIALS using this minimal configuration:

mkdir deps/sundials/build
cd deps/sundials/build
cmake -DCMAKE_INSTALL_PREFIX=../../sundials-install -DENABLE_MPI=ON -DSUNDIALS_INDEX_SIZE=32 ..
make -j install

Instructions for building SUNDIALS with additional options may be found here.

Since each of NumPy, Matplotlib, and Pandas are widely used, it is likely that these are already installed on your system. However, if those are missing or need to be updated, then we recommend that these be installed in a Python virtual environment, as follows:

python3 -m venv .venv
source .venv/bin/activate
cd deps
pip install -r python_requirements.txt

You may "deactivate" this Python environment from your current shell with the command

deactivate

and in the future you can "reactivate" the python environment in your shell by running from the top-level directory of this repository

source .venv/bin/activate

Once the necessary dependencies have been installed, the following CMake variables can be used to configure the build for this repository:

• CMAKE_INSTALL_PREFIX - the path where executables and input files should be installed e.g., my/install/path. The executables will be installed in the bin directory and input files in the tests directory under the given path.

• CMAKE_C_COMPILER - the C compiler to use e.g., mpicc. If not set, CMake will attempt to automatically detect the C compiler.

• CMAKE_C_FLAGS - the C compiler flags to use e.g., -g -O2.

• CMAKE_C_STANDARD - the C standard to use, defaults to 99.

• CMAKE_CXX_COMPILER - the C++ compiler to use e.g., mpicxx. If not set, CMake will attempt to automatically detect the C++ compiler.

• CMAKE_CXX_FLAGS - the C++ flags to use e.g., -g -O2.

• CMAKE_CXX_STANDARD - the C++ standard to use, defaults to 11.

• SUNDIALS_ROOT - the root directory of the SUNDIALS installation, defaults to the value of the SUNDIALS_ROOT environment variable. If not set, CMake will attempt to automatically locate a SUNDIALS install on the system.

• CMAKE_CUDA_COMPILER - the CUDA compiler to use e.g., nvcc. If not set, CMake will attempt to automatically detect the CUDA compiler.

• CMAKE_CUDA_FLAGS - the CUDA compiler flags to use.

• CMAKE_CUDA_ARCHITECTURES - the CUDA architecture to target e.g., 70.

Like most CMake-based projects, in-source builds are not permitted, so the code should be configured and built from a separate build directory, e.g.,

  mkdir frontiers-demonstrations/build
  cd frontiers-demonstrations/build
  cmake -DSUNDIALS_ROOT="[sundials-path] .."
  make -j install

where [sundials-path] is the path to the top-level folder containing the SUNDIALS installation.

If SUNDIALS was installed using the submodule-based instructions above, then the following commands should be sufficient to install the executables into a new frontiers-demonstrations/bin directory:

  mkdir frontiers-demonstrations/build
  cd frontiers-demonstrations/build
  cmake -DSUNDIALS_ROOT=../deps/sundials-install ..
  make -j install