felixmusil / sphericart

Multi-language library for the calculation of spherical harmonics in Cartesian coordinates

sphericart

This is sphericart, a multi-language library for the efficient calculation of the spherical harmonics and their derivatives in Cartesian coordinates.

For instructions and examples on the usage of the library, please refer to our documentation.

Installation

Python API

Pre-built (https://pypi.org/project/sphericart/).

pip install sphericart             # numpy version
pip install sphericart[torch]      # including also the torch bindings

Note that the pre-built packages are compiled for a generic CPU, and might be less performant than they could be on a specific processor. To generate libraries that are optimized for the target system, you can build from source:

git clone https://github.com/lab-cosmo/sphericart
pip install .

# if you also want the torch bindings
pip install .[torch]

# torch bindings, CPU-only version
pip install --extra-index-url https://download.pytorch.org/whl/cpu .[torch]

C and C++ API

From source

git clone https://github.com/lab-cosmo/sphericart
cd sphericart

mkdir build && cd build

cmake .. <cmake configuration options>
cmake --build . --target install

The following cmake configuration options are available:

• -DSPHERICART_BUILD_TORCH=ON/OFF: build the torch bindings in addition to the main library
• -DSPHERICART_BUILD_TESTS=ON/OFF: build C++ unit tests
• -DSPHERICART_OPENMP=ON/OFF: enable OpenMP parallelism
• -DCMAKE_INSTALL_PREFIX=<where/you/want/to/install> set the root path for installation

Running tests and documentation

Tests and the local build of the documentation can be run with tox. The default tests, which are also run on the CI, can be executed by simply running

tox

in the main folder of the repository.

To run tests in a CPU-only environment you can set the environment variable PIP_EXTRA_INDEX_URL before calling tox, e.g.

PIP_EXTRA_INDEX_URL=https://download.pytorch.org/whl/cpu tox -e docs

will build the documentation in a CPU-only environment.