httk.atomistic.models.moments.api
=================================

.. py:module:: httk.atomistic.models.moments.api

.. autoapi-nested-parse::

   The minimal canonical site-moments interface for httk-atomistic.



Classes
-------

.. autoapisummary::

   httk.atomistic.models.moments.api.SiteMomentsAPI


Module Contents
---------------

.. py:class:: SiteMomentsAPI

   Bases: :py:obj:`abc.ABC`


   Abstract base class for the canonical per-site magnetic-moments interface.

   ``cartesian_moments`` is the exact Nx3 Cartesian interchange format, in Bohr magnetons.
   A collinear representation has no axis and therefore raises from that accessor instead of
   fabricating one.


   .. py:property:: cartesian_moments
      :type: httk.core.SurdVector

      :abstractmethod:



   .. py:property:: precision
      :type: fractions.Fraction | None


      How precisely the moments were stated, in Bohr magnetons, or ``None``.

      Concrete rather than abstract, so a backend with no source of precision inherits
      ``None`` instead of breaking.