Source code for spglib.spg

"""SpaceGroup operations."""
# Copyright (C) 2015 Atsushi Togo
# This file is part of spglib.
# SPDX-License-Identifier: BSD-3-Clause

from __future__ import annotations

import dataclasses
import warnings
from typing import Any, cast

import numpy as np
from numpy.typing import ArrayLike, NDArray

import spglib

from . import _spglib
from ._compat.typing import TypeAlias
from ._compat.warnings import deprecated
from .error import _set_no_error, _set_or_throw_error
from .utils import Cell, DictInterface, Lattice, Numbers, Positions, _expand_cell

__all__ = [
    "SpgCell",
    "SpglibDataset",
    "SpaceGroupType",
    "get_symmetry",
    "get_symmetry_dataset",
    "get_spacegroup",
    "get_spacegroup_type",
    "get_spacegroup_type_from_symmetry",
    "get_symmetry_from_database",
    "get_hall_number_from_symmetry",
]


SpgCell: TypeAlias = tuple[Lattice, Positions, Numbers]
"""
Crystal structure represented by a tuple of (:py:type:`spglib.utils.Lattice`,
:py:type:`spglib.utils.Positions`, :py:type:`spglib.utils.Numbers`).
"""


[docs] @dataclasses.dataclass(eq=False, frozen=True) class SpglibDataset(DictInterface): """Spglib dataset information. .. versionadded:: 1.9.4 The member 'choice' is added. .. versionadded:: 2.5.0 """ number: int """International space group number""" hall_number: int """Hall number. This number is used in :func:`get_symmetry_from_database` and :func:`get_spacegroup_type`. """ international: str """International symbol""" hall: str """Hall symbol""" choice: str """Centring, origin, basis vector setting""" transformation_matrix: NDArray[np.double] """Transformation matrix from input lattice to standardized lattice. shape=(3, 3), order='C', dtype='double' .. code-block:: L^original = L^standardized * Tmat. See the detail at :ref:`dataset_origin_shift_and_transformation`. """ origin_shift: NDArray[np.double] """Origin shift from standardized to input origin. shape=(3,), dtype='double' See the detail at :ref:`dataset_origin_shift_and_transformation`. """ rotations: NDArray[np.intc] """Matrix (rotation) parts of space group operations. shape=(n_operations, 3, 3), order='C', dtype='intc' .. note:: Space group operations are obtained by .. code-block:: python [(r,t) for r, t in zip(rotations, translations)] See also :func:`get_symmetry`. """ translations: NDArray[np.double] """Vector (translation) parts of space group operations. shape=(n_operations, 3), order='C', dtype='double' .. note:: Space group operations are obtained by .. code-block:: python [(r,t) for r, t in zip(rotations, translations)] See also :func:`get_symmetry`. """ wyckoffs: list[str] """Wyckoff letters corresponding to the space group type.""" site_symmetry_symbols: list[str] """Site symmetry symbols corresponding to the space group type.""" crystallographic_orbits: NDArray[np.intc] """Symmetrically equivalent atoms, where 'symmetrically' means the space group operations corresponding to the space group type. This is very similar to ``equivalent_atoms``. See the difference explained in ``equivalent_atoms`` shape=(n_atoms,), dtype='intc' """ equivalent_atoms: NDArray[np.intc] """Symmetrically equivalent atoms, where 'symmetrically' means found symmetry operations. shape=(n_atoms,), dtype='intc' In spglib, symmetry operations are given for the input cell. When a non-primitive cell is inputted and the lattice made by the non-primitive basis vectors breaks its point group, the found symmetry operations may not correspond to the crystallographic space group type. """ # Primitive cell primitive_lattice: NDArray[np.double] """Basis vectors a, b, c of a primitive cell in row vectors. shape=(3, 3), order='C', dtype='double' This is the primitive cell found inside spglib before applying standardization. Therefore, the values are distorted with respect to found space group type. """ mapping_to_primitive: NDArray[np.intc] """Atom index mapping from original cell to the primitive cell of ``primitive_lattice``. shape=(n_atoms), dtype='intc' """ # Idealized standardized unit cell std_lattice: NDArray[np.double] """Basis vectors a, b, c of an idealized standardized cell in row vectors. shape=(3, 3), order='C', dtype='double' """ std_positions: NDArray[np.double] """Positions of atoms in the standardized cell in fractional coordinates. shape=(n_atoms, 3), order='C', dtype='double' """ std_types: NDArray[np.intc] """Identity numbers of atoms in the standardized cell. shape=(n_atoms,), dtype='intc' """ std_rotation_matrix: NDArray[np.double] """Rigid rotation matrix to rotate from standardized basis vectors to idealized standardized orthonormal basis vectors. shape=(3, 3), order='C', dtype='double' .. code-block:: L^idealized = R * L^standardized. See the detail at :ref:`dataset_idealized_cell`. """ std_mapping_to_primitive: NDArray[np.intc] """``std_positions`` index mapping to those of atoms of the primitive cell in the standardized cell.""" pointgroup: str """Pointgroup symbol in Hermann-Mauguin notation."""
[docs] @dataclasses.dataclass(eq=True, frozen=True) class SpaceGroupType(DictInterface): """Space group type information. More details are found at :ref:`spglib-dataset`. .. versionchanged:: 2.0 ``hall_number`` member is added. .. versionadded:: 2.5.0 """ number: int """International space group number""" international_short: str """International short symbol""" international_full: str """International full symbol""" international: str """International symbol""" schoenflies: str """Schoenflies symbol""" hall_number: int """Hall symbol serial number""" hall_symbol: str """Hall symbol""" choice: str """Centring, origin, basis vector setting""" pointgroup_international: str """International symbol of crystallographic point group""" pointgroup_schoenflies: str """Schoenflies symbol of crystallographic point group""" arithmetic_crystal_class_number: int """Arithmetic crystal class number""" arithmetic_crystal_class_symbol: str """Arithmetic crystal class symbol"""
[docs] def get_symmetry( cell: Cell, symprec: float = 1e-5, angle_tolerance: float = -1.0, mag_symprec: float = -1.0, is_magnetic: bool = True, ) -> dict[str, Any] | None: r"""Find symmetry operations from a crystal structure and site tensors. .. warning:: :func:`get_symmetry` with ``is_magnetic=True`` is deprecated at version 2.0. Use :func:`get_magnetic_symmetry` for magnetic symmetry search. Parameters ---------- cell : tuple Crystal structure given in tuple. It has to follow the following form, (basis vectors, atomic points, types in integer numbers, ...) - basis vectors : array_like shape=(3, 3), order='C', dtype='double' .. code-block:: python [[a_x, a_y, a_z], [b_x, b_y, b_z], [c_x, c_y, c_z]] - atomic points : array_like shape=(num_atom, 3), order='C', dtype='double' Atomic position vectors with respect to basis vectors, i.e., given in fractional coordinates. - types : array_like shape=(num_atom, ), dtype='intc' Integer numbers to distinguish species. - optional data : case-I: Scalar shape=(num_atom, ), dtype='double' Each atomic site has a scalar value. With is_magnetic=True, values are included in the symmetry search in a way of collinear magnetic moments. case-II: Vectors shape=(num_atom, 3), order='C', dtype='double' Each atomic site has a vector. With is_magnetic=True, vectors are included in the symmetry search in a way of non-collinear magnetic moments. symprec : float Symmetry search tolerance in the unit of length. angle_tolerance : float Symmetry search tolerance in the unit of angle deg. Normally it is not recommended to use this argument. See a bit more detail at :ref:`variables_angle_tolerance`. If the value is negative, an internally optimized routine is used to judge symmetry. mag_symprec : float Tolerance for magnetic symmetry search in the unit of magnetic moments. If not specified, use the same value as symprec. is_magnetic : bool When optional data (4th element of cell tuple) is given in case-II, the symmetry search is performed considering magnetic symmetry, which may be corresponding to that for non-collinear calculation. Default is True, but this does nothing unless optional data is supplied. Returns ------- symmetry: dict Rotation parts and translation parts of symmetry operations are represented with respect to basis vectors. When the search failed, :code:`None` is returned. - 'rotations' : ndarray shape=(num_operations, 3, 3), order='C', dtype='intc' Rotation (matrix) parts of symmetry operations - 'translations' : ndarray shape=(num_operations, 3), dtype='double' Translation (vector) parts of symmetry operations - 'time_reversals': ndarray (exists when the optional data is given) shape=(num_operations, ), dtype='bool\_' Time reversal part of magnetic symmetry operations. True indicates time reversal operation, and False indicates an ordinary operation. - 'equivalent_atoms' : ndarray shape=(num_atoms, ), dtype='intc' A mapping table of atoms to symmetrically independent atoms. This is used to find symmetrically equivalent atoms. The numbers contained are the indices of atoms starting from 0, i.e., the first atom is numbered as 0, and then 1, 2, 3, ... :code:`np.unique(equivalent_atoms)` gives representative symmetrically independent atoms. A list of atoms that are symmetrically equivalent to some independent atom (here for example 1 is in :code:`equivalent_atom`) is found by :code:`np.where(equivalent_atom=1)[0]`. Notes ----- The orders of the rotation matrices and the translation vectors correspond with each other, e.g. , the second symmetry operation is organized by the set of the second rotation matrix and second translation vector in the respective arrays. Therefore a set of symmetry operations may obtained by .. code-block:: python [(r, t) for r, t in zip(dataset['rotations'], dataset['translations'])] The operations are given with respect to the fractional coordinates (not for Cartesian coordinates). The rotation matrix and translation vector are used as follows: .. code-block:: new_vector[3x1] = rotation[3x3] * vector[3x1] + translation[3x1] The three values in the vector are given for the a, b, and c axes, respectively. """ _set_no_error() _, _, _, magmoms = _expand_cell(cell) if magmoms is None: # Get symmetry operations without on-site tensors (i.e. normal crystal) try: dataset = get_symmetry_dataset( cast(SpgCell, cell), symprec=symprec, angle_tolerance=angle_tolerance, _throw=True, ) except Exception as exc: _set_or_throw_error(exc) return None return { "rotations": dataset.rotations, "translations": dataset.translations, "equivalent_atoms": dataset.equivalent_atoms, } else: warnings.warn( "Use get_magnetic_symmetry() for cell with magnetic moments.", DeprecationWarning, stacklevel=1, ) try: return spglib.get_magnetic_symmetry( cast(spglib.MsgCell, cell), symprec=symprec, angle_tolerance=angle_tolerance, mag_symprec=mag_symprec, is_axial=None, with_time_reversal=is_magnetic, _throw=True, ) except Exception as exc: _set_or_throw_error(exc) return None
[docs] def get_symmetry_dataset( cell: SpgCell, symprec: float = 1e-5, angle_tolerance: float = -1.0, hall_number: int = 0, _throw: bool = False, ) -> SpglibDataset | None: """Search symmetry dataset from an input cell. Parameters ---------- cell, symprec, angle_tolerance: See :func:`get_symmetry`. hall_number : int If a serial number of Hall symbol (>0) is given, the database corresponding to the Hall symbol is made. The mapping from Hall symbols to a space-group-type is the many-to-one mapping. Without specifying this option (i.e., in the case of ``hall_number=0``), always the first one (the smallest serial number corresponding to the space-group-type in [list of space groups (Seto's web site)](https://yseto.net/en/sg/sg1)) among possible choices and settings is chosen as default. This argument is useful when the other choice (or setting) is expected to be hooked. This affects to the obtained values of `international`, `hall`, `choice`, `transformation_matrix`, `origin shift`, `wyckoffs`, `std_lattice`, `std_positions`, `std_types` and `std_rotation_matrix`, but not to `rotations` and `translations` since the later set is defined with respect to the basis vectors of user's input (the `cell` argument). See also :ref:`dataset_spg_get_dataset_spacegroup_type`. Returns ------- dataset: :class:`SpglibDataset` | None If it fails, None is returned. Otherwise a dictionary is returned. More details are found at :ref:`spglib-dataset`. """ _set_no_error(_throw) lattice, positions, numbers, _ = _expand_cell(cell) try: spg_ds = _spglib.dataset( lattice, positions, numbers, int(hall_number), float(symprec), float(angle_tolerance), ) except Exception as exc: _set_or_throw_error(exc, _throw) return None return SpglibDataset(**spg_ds)
[docs] def get_spacegroup( cell: SpgCell, symprec: float = 1e-5, angle_tolerance: float = -1.0, symbol_type: int = 0, ) -> str | None: """Return space group in international table symbol and number as a string. With ``symbol_type=1``, Schoenflies symbol is given instead of international symbol. :rtype: str | None :return: If it fails, None is returned. """ _set_no_error() try: dataset = get_symmetry_dataset( cell, symprec=symprec, angle_tolerance=angle_tolerance, _throw=True, ) except Exception as exc: _set_or_throw_error(exc) return None try: spg_type = get_spacegroup_type(dataset.hall_number, _throw=True) except Exception as exc: _set_or_throw_error(exc) return None if symbol_type == 1: return f"{spg_type.schoenflies} ({dataset.number})" else: return f"{spg_type.international_short} ({dataset.number})"
[docs] def get_spacegroup_type( hall_number: int, _throw: bool = False, ) -> SpaceGroupType | None: """Translate Hall number to space group type information. If it fails, return None. This function allows to directly access to the space-group-type database in spglib (spg_database.c). To specify the space group type with a specific choice, ``hall_number`` is used. The definition of ``hall_number`` is found at :ref:`dataset_spg_get_dataset_spacegroup_type`. :param hall_number: Serial number for Hall symbol :return: :class:`SpaceGroupType` or None .. versionadded:: 1.9.4 """ _set_no_error(_throw) try: spg_type = _spglib.spacegroup_type(int(hall_number)) except Exception as exc: _set_or_throw_error(exc, _throw) return None return SpaceGroupType(**spg_type)
[docs] def get_spacegroup_type_from_symmetry( rotations: ArrayLike[np.intc], translations: ArrayLike[np.double], lattice: ArrayLike[np.double] | None = None, symprec: float = 1e-5, ) -> SpaceGroupType | None: """Return space-group type information from symmetry operations. This is expected to work well for the set of symmetry operations whose distortion is small. The aim of making this feature is to find space-group-type for the set of symmetry operations given by the other source than spglib. Parameters ---------- rotations : array_like Matrix parts of space group operations. shape=(n_operations, 3, 3), order='C', dtype='intc' translations : array_like Vector parts of space group operations. shape=(n_operations, 3), order='C', dtype='double' lattice : array_like, optional Basis vectors a, b, c given in row vectors. Default is None, which gives unit matrix. This should be the same as that used to find ``rotations`` and ``translations``. If it is unknown, the cubic basis vector may be a possible choice unless the ``rotations`` and ``translations`` were obtained for an unusual (very oblique) choice of basis vectors. shape=(3, 3), order='C', dtype='double' symprec: float See :func:`get_symmetry`. Returns ------- spacegroup_type : :class:`SpaceGroupType` or None Notes ----- .. versionadded:: 2.0 This is the replacement of :func:`get_hall_number_from_symmetry`. """ r = np.array(rotations, dtype="intc", order="C") t = np.array(translations, dtype="double", order="C") if lattice is None: _lattice = np.eye(3, dtype="double", order="C") else: _lattice = np.array(np.transpose(lattice), dtype="double", order="C") _set_no_error() try: spg_type = _spglib.spacegroup_type_from_symmetry(r, t, _lattice, float(symprec)) except Exception as exc: _set_or_throw_error(exc) return None return SpaceGroupType(**spg_type)
[docs] def get_symmetry_from_database(hall_number: int) -> dict[str, Any] | None: """Return symmetry operations corresponding to a Hall symbol. If fails, return None. Parameters ---------- hall_number : int The Hall symbol is given by the serial number in between 1 and 530. The definition of ``hall_number`` is found at :ref:`dataset_spg_get_dataset_spacegroup_type`. Returns ------- symmetry : dict - rotations Rotation parts of symmetry operations corresponding to ``hall_number``. - translations Translation parts of symmetry operations corresponding to ``hall_number``. """ _set_no_error() rotations = np.zeros((192, 3, 3), dtype="intc") translations = np.zeros((192, 3), dtype="double") try: num_sym = _spglib.symmetry_from_database( rotations, translations, int(hall_number), ) except Exception as exc: _set_or_throw_error(exc) return None return { "rotations": np.array(rotations[:num_sym], dtype="intc", order="C"), "translations": np.array(translations[:num_sym], dtype="double", order="C"), }
[docs] @deprecated("Use get_spacegroup_type_from_symmetry instead") def get_hall_number_from_symmetry( rotations: ArrayLike[np.intc], translations: ArrayLike[np.double], symprec: float = 1e-5, ) -> int | None: """Hall number is obtained from a set of symmetry operations. If fails, return None. .. deprecated:: 2.0 Replaced by {func}`get_spacegroup_type_from_symmetry`. Return one of ``hall_number`` corresponding to a space-group type of the given set of symmetry operations. When multiple ``hall_number`` exist for the space-group type, the smallest one (the first description of the space-group type in International Tables for Crystallography) is chosen. The definition of ``hall_number`` is found at :ref:`dataset_spg_get_dataset_spacegroup_type` and the corresponding space-group-type information is obtained through {func}`get_spacegroup_type`. This is expected to work well for the set of symmetry operations whose distortion is small. The aim of making this feature is to find space-group-type for the set of symmetry operations given by the other source than spglib. Note that the definition of ``symprec`` is different from usual one, but is given in the fractional coordinates and so it should be small like ``1e-5``. """ _set_no_error() r = np.array(rotations, dtype="intc", order="C") t = np.array(translations, dtype="double", order="C") try: hall_number = _spglib.hall_number_from_symmetry(r, t, float(symprec)) except Exception as exc: _set_or_throw_error(exc) return None return hall_number