Notes
This release contains two new QMC features and numerous "behind the scenes" updates to improve both QMCPACK and Nexus. As detailed in the Nexus section, most notably, Nexus is now fully installable as a Python package and the Python-based testing now uses pytest. The QMCPACK CMake has been updated consistently. Tests will be created provided the necessary packages are available otherwise a message is printed and the tests are skipped. Feedback is welcomed.
- Upcoming breaking change: Classic/non-batched drivers will be removed in a future release. See https://qmcpack.readthedocs.io/en/develop/performance_portable.html for instructions on using the batched/performance portable drivers. We recommend that all new projects should only use the batched drivers. For compatibility with future QMCPACK versions, verify that all new QMCPACK input XML and Nexus scripts explicitly request batched drivers.
- Energy density supported in batched code (CPU only) #5865
- New developmental features to share splines between processes to reduce memory usage. This feature (spline distributed_ranks, shared_ranks) allows the large spline data buffers to be shared between MPI processes within a node, potentially significantly reducing overall CPU memory usage. This CPU feature will be expanded in future versions to support more complex sharing arrangements. Shared splines between GPUs is also under development. While these features are being enhanced, please contact developers for more information on how to best use them. #5908, #5889
- Citations for table method and delayed update are now included in the output. Please advise where any additional references would be useful. #5938
- CUDA minimum version updated 12.3 #5876
- Several Python helper and testing scripts have been updated to modern Python 3 and package versions. Please report any files that still need updates.
- Development container updated to include PySCF 2.13.0 #5956
- Fix bounds error in MPC spline evaluation #5830
- Various documentation and build recipe updates, minor bug fixes and quality of life improvements.
NEXUS [2.3.0]
Nexus is updated to be a standard Python package for easier use and installation. e.g. Nexus and all dependencies are now straightforwardly installable with uv or pip. See e.g. Installing Nexus with uv. Existing use and installation methods will continue to be supported. The test infrastructure has also been fully updated to use the standard pytest and coverage.py packages.
- Python >= 3.10 is a minimum requirement. Use e.g. uv, spack, or a system package manager to get a newer Python if needed.
- Installable as a Python package #5742
- Nexus "executables" (qmca, qdens, nxs-sim etc.) are directly usable via the installed package. #5851
- Testing moved to pytest #5894, #5924. This included many updates to files handling throuhghout, e.g. #5943.
- Improved error handling and messaging, e.g. #5985, #5981
- Several edge case bug fixes and refinements, e.g. #5960, #5972
- Checkpoint setting supported in generate_qmcpack #5869
- Updated manual install script #5870
- Added
pathlib.Pathsupport throughout, e.g. #5937 uv.lockfile for developers #5885- Refactoring and cleanup throughout.