PythMPG¶

PythMPG is a Magnetic Point Group (MPG) tensor analysis toolkit.

This python package provides tools to enumerate symmetry properties of all 122 magnetic point groups and to count the number of independent components of arbitrary-rank tensors under those symmetries, as classified by their Jahn symbol.

A major feature of the package is its ability to export data in the form of a .csv file that can be used to build a spreadsheet capable of screening for MPGs based on whether they have certain symmetries or support specied tensor properties. A broader community of users can then use standard spreadsheet tools, such as sorting on columns and hiding columns and rows, to achieve similar ends, without the need to access the python codes themselves.

Modules in the Package¶

spreadsheet: Defines Spreadsheet, the primary user-facing class.
mpg_tools: Functions get_mpg_info() and get_num_indep() for querying MPG symmetry properties and tensor independence counts.
mpg_dicts: Module-level dictionaries describing all 122 MPGs, their generators, and BNS serial numbers. Built on first import.
pg_elements: Constructs rotation matrices and multiplication tables for the hexagonal and cubic crystallographic point groups.
parse_jahn: Parser for Jahn symbols that encodes index-symmetrization instructions for arbitrary-rank tensors.

Installation¶

PythMPG is available through PyPI:

pip install pythmpg

To install from source in editable mode:

git clone https://github.com/pythmpg/pythmpg.git
cd pythmpg
pip install -e .

PythMPG ≥ 1.0.0 requires Python ≥ 3.12 and numpy ≥ 2.0

Citation¶

The principal reference describing the code is Andrea Urru, Turan Birol, Trey Cole, and David Vanderbilt, Screening of tensor properties by magnetic point group symmetries: The pythmpg code package, https://arxiv.org/abs/2610.10024, 2026.

The spreadsheets and code are also available at this Zenodo repository, which can be cited in Bibtex and other formats using the Export tab on the landing page.

License¶

This software is released under the GNU General Public License v3.0.