Source code for spglib.spglib

"""Python bindings for C library for finding and handling crystal."""
# Copyright (C) 2015 Atsushi Togo
# All rights reserved.
#
# This file is part of spglib.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# * Redistributions of source code must retain the above copyright
#   notice, this list of conditions and the following disclaimer.
#
# * Redistributions in binary form must reproduce the above copyright
#   notice, this list of conditions and the following disclaimer in
#   the documentation and/or other materials provided with the
#   distribution.
#
# * Neither the name of the spglib project nor the names of its
#   contributors may be used to endorse or promote products derived
#   from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
# COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.

from __future__ import annotations

import dataclasses
import sys
import warnings

if sys.version_info < (3, 9):
    from typing import Mapping
else:
    from collections.abc import Mapping
from typing import TYPE_CHECKING

import numpy as np

try:
    from . import _spglib  # type: ignore[attr-defined]
except ImportError:
    import sys

    if sys.version_info < (3, 10):
        from importlib_resources import as_file, files
    else:
        from importlib.resources import as_file, files
    from ctypes import cdll

    root = files("spglib.lib")
    for file in root.iterdir():
        if "symspg." in file.name:
            with as_file(file) as bundled_lib:
                try:
                    cdll.LoadLibrary(str(bundled_lib))
                    from . import _spglib  # type: ignore[attr-defined]

                    break
                except ImportError as err:
                    raise FileNotFoundError(
                        "Could not load bundled Spglib C library"
                    ) from err
    else:
        raise FileNotFoundError(
            "Spglib C library is not installed and no bundled version was detected"
        )


if TYPE_CHECKING:
    import sys
    from collections.abc import Iterator, Sequence
    from typing import Any

    from numpy.typing import ArrayLike

    if sys.version_info < (3, 10):
        from typing_extensions import TypeAlias
    else:
        from typing import TypeAlias

    Lattice: TypeAlias = Sequence[Sequence[float]]
    Positions: TypeAlias = Sequence[Sequence[float]]
    Numbers: TypeAlias = Sequence[int]
    Magmoms: TypeAlias = Sequence[float] | Sequence[Sequence[float]]
    Cell: TypeAlias = (
        tuple[Lattice, Positions, Numbers] | tuple[Lattice, Positions, Numbers, Magmoms]
    )

warnings.filterwarnings(
    "module", category=DeprecationWarning, message=r"dict interface.*"
)


class SpglibError:
    """Error message why spglib failed."""

    message = "no error"


spglib_error = SpglibError()


@dataclasses.dataclass(eq=True, frozen=True)
class DictInterface(Mapping[str, "Any"]):
    """Base class for dataclass with dict interface.

    .. versionadded:: 2.5.0
    .. deprecated:: 2.5.0
        Dict-like interface (``obj['field']``) are deprecated.
        Please use attribute interface instead (``obj.field``)
    """

    def __getitem__(self, key: str) -> Any:
        """Return the value of the key."""
        warnings.warn(
            f"dict interface ({self.__class__.__name__}['{key}']) is deprecated."
            "Use attribute interface ({self.__class__.__name__}.{key}) instead",
            DeprecationWarning,
        )
        return dataclasses.asdict(self)[key]

    def __len__(self) -> int:
        """Return the number of fields."""
        return len(dataclasses.fields(self))

    def __iter__(self) -> Iterator[str]:
        """Return an iterator over the keys."""
        return iter(dataclasses.asdict(self))


[docs] @dataclasses.dataclass(eq=True, frozen=True) class SpaceGroupType(DictInterface): """Space group type information. .. 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] @dataclasses.dataclass(eq=True, frozen=True) class MagneticSpaceGroupType(DictInterface): """Magnetic space group type information. .. versionadded:: 2.5.0 """ uni_number: int """Serial number of UNI (or BNS) symbols""" litvin_number: int """Serial number in Litvin's [Magnetic group tables](https://www.iucr.org/publ/978-0-9553602-2-0)""" bns_number: str """BNS number e.g. '151.32'""" og_number: str """OG number e.g. '153.4.1270'""" number: int """ITA's serial number of space group for reference setting""" type: int """Type of MSG from 1 to 4"""
[docs] def get_version(): """Return version number of spglib with tuple of three numbers. .. versionadded:: 1.8.3 .. deprecated:: 2.3.0 Use :py:func:`spg_get_version` and ``spglib.__version__`` instead """ warnings.warn( "get_version() is deprecated. Use __version__ for the python binding" "version and get_spg_version for the detected spglib library version.", DeprecationWarning, ) _set_no_error() return _spglib.version_tuple()
[docs] def spg_get_version(): """Get the X.Y.Z version of the detected spglib C library. .. versionadded:: 2.3.0 :return: version string """ _set_no_error() return _spglib.version_string()
[docs] def spg_get_version_full(): """Get the full version of the detected spglib C library. .. versionadded:: 2.3.0 :return: full version string """ _set_no_error() return _spglib.version_full()
[docs] def spg_get_commit(): """Get the commit of the detected spglib C library. .. versionadded:: 2.3.0 :return: commit string """ _set_no_error() return _spglib.commit()
[docs] def get_symmetry( cell: Cell, symprec=1e-5, angle_tolerance=-1.0, mag_symprec=-1.0, is_magnetic=True, ) -> dict | 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) dataset = get_symmetry_dataset( cell, symprec=symprec, angle_tolerance=angle_tolerance, ) if dataset is None: _set_error_message() 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, ) return get_magnetic_symmetry( cell, symprec=symprec, angle_tolerance=angle_tolerance, mag_symprec=mag_symprec, is_axial=None, with_time_reversal=is_magnetic, )
[docs] def get_magnetic_symmetry( cell: Cell, symprec=1e-5, angle_tolerance=-1.0, mag_symprec=-1.0, is_axial=None, with_time_reversal=True, ) -> dict | None: r"""Find magnetic symmetry operations from a crystal structure and site tensors. Parameters ---------- cell : tuple Crystal structure given either in tuple. In the case given by a tuple, it has to follow the form below, (basis vectors, atomic points, types in integer numbers, ...) - basis vectors : array_like shape=(3, 3), order='C', dtype='double' .. code-block:: [[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. - magmoms: 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_axial: None or bool Set `is_axial=True` if `magmoms` does not change their sign by improper rotations. If not specified, set `is_axial=False` when `magmoms.shape==(num_atoms, )`, and set `is_axial=True` when `magmoms.shape==(num_atoms, 3)`. These default settings correspond to collinear and non-collinear spins. with_time_reversal: bool Set `with_time_reversal=True` if `magmoms` change their sign by time-reversal operations. Default is True. Returns ------- symmetry: dict or None Rotation parts and translation parts of symmetry operations represented with respect to basis vectors and atom index mapping by symmetry operations. - '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 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' Notes ----- .. versionadded:: 2.0 """ _set_no_error() lattice, positions, numbers, magmoms = _expand_cell(cell) if magmoms is None: raise TypeError("Specify magnetic moments in cell.") max_size = len(positions) * 96 rotations = np.zeros((max_size, 3, 3), dtype="intc", order="C") translations = np.zeros((max_size, 3), dtype="double", order="C") equivalent_atoms = np.zeros(len(magmoms), dtype="intc") primitive_lattice = np.zeros((3, 3), dtype="double", order="C") # (magmoms.ndim - 1) has to be equal to the rank of physical # tensors, e.g., ndim=1 for collinear, ndim=2 for non-collinear. if magmoms.ndim == 1 or magmoms.ndim == 2: spin_flips = np.zeros(max_size, dtype="intc") else: spin_flips = None # Infer is_axial value from tensor_rank to keep backward compatibility if is_axial is None: if magmoms.ndim == 1: is_axial = False # Collinear spin elif magmoms.ndim == 2: is_axial = True # Non-collinear spin num_sym = _spglib.symmetry_with_site_tensors( rotations, translations, equivalent_atoms, primitive_lattice, spin_flips, lattice, positions, numbers, magmoms, with_time_reversal * 1, is_axial * 1, symprec, angle_tolerance, mag_symprec, ) if num_sym == 0: _set_error_message() return None else: spin_flips = np.array(spin_flips[:num_sym], dtype="intc", order="C") # True for time reversal operation, False for ordinary operation time_reversals = spin_flips == -1 return { "rotations": np.array(rotations[:num_sym], dtype="intc", order="C"), "translations": np.array(translations[:num_sym], dtype="double", order="C"), "time_reversals": time_reversals, "equivalent_atoms": equivalent_atoms, "primitive_lattice": np.array( np.transpose(primitive_lattice), dtype="double", order="C", ), }
def _build_dataset_dict(spg_ds): keys = ( "number", "hall_number", "international", "hall", "choice", "transformation_matrix", "origin_shift", "rotations", "translations", "wyckoffs", "site_symmetry_symbols", "crystallographic_orbits", "equivalent_atoms", "primitive_lattice", "mapping_to_primitive", "std_lattice", "std_types", "std_positions", "std_rotation_matrix", "std_mapping_to_primitive", # 'pointgroup_number', "pointgroup", ) dataset = {} for key, data in zip(keys, spg_ds): dataset[key] = data dataset["international"] = dataset["international"].strip() dataset["hall"] = dataset["hall"].strip() dataset["choice"] = dataset["choice"].strip() dataset["transformation_matrix"] = np.array( dataset["transformation_matrix"], dtype="double", order="C", ) dataset["origin_shift"] = np.array(dataset["origin_shift"], dtype="double") dataset["rotations"] = np.array(dataset["rotations"], dtype="intc", order="C") dataset["translations"] = np.array( dataset["translations"], dtype="double", order="C", ) letters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" dataset["wyckoffs"] = [letters[x] for x in dataset["wyckoffs"]] dataset["site_symmetry_symbols"] = [ s.strip() for s in dataset["site_symmetry_symbols"] ] dataset["crystallographic_orbits"] = np.array( dataset["crystallographic_orbits"], dtype="intc", ) dataset["equivalent_atoms"] = np.array(dataset["equivalent_atoms"], dtype="intc") dataset["primitive_lattice"] = np.array( np.transpose(dataset["primitive_lattice"]), dtype="double", order="C", ) dataset["mapping_to_primitive"] = np.array( dataset["mapping_to_primitive"], dtype="intc", ) dataset["std_lattice"] = np.array( np.transpose(dataset["std_lattice"]), dtype="double", order="C", ) dataset["std_types"] = np.array(dataset["std_types"], dtype="intc") dataset["std_positions"] = np.array( dataset["std_positions"], dtype="double", order="C", ) dataset["std_rotation_matrix"] = np.array( dataset["std_rotation_matrix"], dtype="double", order="C", ) dataset["std_mapping_to_primitive"] = np.array( dataset["std_mapping_to_primitive"], dtype="intc", ) dataset["pointgroup"] = dataset["pointgroup"].strip() return dataset
[docs] def get_symmetry_dataset( cell: Cell, symprec=1e-5, angle_tolerance=-1.0, hall_number=0, ) -> dict | 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/?page_id=29%3E)) 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: dict If it fails, None is returned. Otherwise a dictionary is returned. More details are found at :ref:`spglib-dataset`. - number : int International space group number. - international : str International symbol. - hall : str Hall symbol. - choice : str Centring, origin, basis vector setting. - hall_number: int Hall number. This number is used in :func:`get_symmetry_from_database` and :func:`get_spacegroup_type`. - transformation_matrix : ndarray shape=(3, 3), order='C', dtype='double' Transformation matrix from input lattice to standardized lattice: .. code-block:: L^original = L^standardized * Tmat. See the detail at :ref:`dataset_origin_shift_and_transformation`. - origin shift : ndarray shape=(3,), dtype='double' Origin shift from standardized to input origin. See the detail at :ref:`dataset_origin_shift_and_transformation`. - rotations : ndarray shape=(n_operations, 3, 3), order='C', dtype='intc' Matrix (rotation) parts of space group operations. 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 shape=(n_operations, 3), order='C', dtype='double' Vector (translation) parts of space group operations. 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. - equivalent_atoms : ndarray shape=(n_atoms,), dtype='intc' Symmetrically equivalent atoms, where 'symmetrically' means found symmetry operations. 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. - crystallographic_orbits : ndarray shape=(n_atoms,), dtype='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`` - Primitive cell : - primitive_lattice : ndarray shape=(3, 3), order='C', dtype='double' Basis vectors a, b, c of a primitive cell in row vectors. 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 shape=(n_atoms), dtype='intc' Atom index mapping from original cell to the primitive cell of ``primitive_lattice``. - Idealized standardized unit cell : - std_lattice : ndarray shape=(3, 3), order='C', dtype='double' Basis vectors a, b, c of a standardized cell in row vectors. - std_positions : ndarray shape=(n_atoms, 3), order='C', dtype='double' Positions of atoms in the standardized cell in fractional coordinates. - std_types : ndarray shape=(n_atoms,), dtype='intc' Identity numbers of atoms in the standarzied cell. - std_rotation_matrix : ndarray shape=(3, 3), order='C', dtype='double' Rigid rotation matrix to rotate from standardized basis vectors to idealized standardized basis vectors. Orthonormalized. .. code-block:: L^idealized = R * L^standardized. See the detail at :ref:`dataset_idealized_cell`. - std_mapping_to_primitive : dtype='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. Notes ----- .. versionadded:: 1.9.4 The member 'choice' is added. """ _set_no_error() lattice, positions, numbers, _ = _expand_cell(cell) spg_ds = _spglib.dataset( lattice, positions, numbers, hall_number, symprec, angle_tolerance, ) if spg_ds is None: _set_error_message() return None dataset = _build_dataset_dict(spg_ds) return dataset
def get_symmetry_layerdataset(cell: Cell, aperiodic_dir=2, symprec=1e-5): """TODO: Add comments.""" _set_no_error() lattice, positions, numbers, _ = _expand_cell(cell) spg_ds = _spglib.layerdataset( lattice, positions, numbers, aperiodic_dir, symprec, ) if spg_ds is None: _set_error_message() return None dataset = _build_dataset_dict(spg_ds) return dataset
[docs] def get_magnetic_symmetry_dataset( cell: Cell, is_axial=None, symprec=1e-5, angle_tolerance=-1.0, mag_symprec=-1.0, ) -> dict | None: """Search magnetic symmetry dataset from an input cell. If it fails, return None. The description of its keys is given at :ref:`magnetic_spglib_dataset`. Parameters ---------- cell, is_axial, symprec, angle_tolerance, mag_symprec: See :func:`get_magnetic_symmetry`. Returns ------- dataset : dict or None Dictionary keys are as follows: Magnetic space-group type - uni_number: int UNI number between 1 to 1651 - msg_type: int Magnetic space groups (MSG) is classified by its family space group (FSG) and maximal space subgroup (XSG). FSG is a non-magnetic space group obtained by ignoring time-reversal term in MSG. XSG is a space group obtained by picking out non time-reversal operations in MSG. - msg_type==1 (type-I): MSG, XSG, FSG are all isomorphic. - msg_type==2 (type-II): XSG and FSG are isomorphic, and MSG is generated from XSG and pure time reversal operations. - msg_type==3 (type-III): XSG is a proper subgroup of MSG with isomorphic translational subgroups. - msg_type==4 (type-IV): XSG is a proper subgroup of MSG with isomorphic point group. - hall_number: int For type-I, II, III, Hall number of FSG; for type-IV, that of XSG - tensor_rank: int Magnetic symmetry operations - n_operations: int - rotations: array, (n_operations, 3, 3) Rotation (matrix) parts of symmetry operations - translations: array, (n_operations, 3) Translation (vector) parts of symmetry operations - time_reversals: array, (n_operations, ) Time reversal part of magnetic symmetry operations. True indicates time reversal operation, and False indicates an ordinary operation. Equivalent atoms - n_atoms: int - equivalent_atoms: array See the docstring of get_symmetry_dataset Transformation to standardized setting - transformation_matrix: array, (3, 3) Transformation matrix from input lattice to standardized - origin_shift: array, (3, ) Origin shift from standardized to input origin Standardized crystal structure - n_std_atoms: int Number of atoms in standardized unit cell - std_lattice: array, (3, 3) Row-wise lattice vectors - std_types: array, (n_std_atoms, ) - std_positions: array, (n_std_atoms, 3) - std_tensors: array (n_std_atoms, ) for collinear magnetic moments. (n_std_atoms, 3) for vector non-collinear magnetic moments. - std_rotation_matrix Rigid rotation matrix to rotate from standardized basis vectors to idealized standardized basis vectors Intermediate data in symmetry search - primitive_lattice: array, (3, 3) Notes ----- .. versionadded:: 2.0 """ # noqa: E501 _set_no_error() lattice, positions, numbers, magmoms = _expand_cell(cell) tensor_rank = magmoms.ndim - 1 # If is_axial is not specified, select collinear or non-collinear spin cases if is_axial is None: if tensor_rank == 0: is_axial = False # Collinear spin elif tensor_rank == 1: is_axial = True # Non-collinear spin spg_ds = _spglib.magnetic_dataset( lattice, positions, numbers, magmoms, tensor_rank, is_axial, symprec, angle_tolerance, mag_symprec, ) if spg_ds is None: _set_error_message() return None keys = ( # Magnetic space-group type "uni_number", "msg_type", "hall_number", "tensor_rank", # Magnetic symmetry operations "n_operations", "rotations", "translations", "time_reversals", # Equivalent atoms "n_atoms", "equivalent_atoms", # Transformation to standardized setting "transformation_matrix", "origin_shift", # Standardized crystal structure "n_std_atoms", "std_lattice", "std_types", "std_positions", "std_tensors", "std_rotation_matrix", # Intermediate datum in symmetry search "primitive_lattice", ) dataset = {} for key, data in zip(keys, spg_ds): dataset[key] = data dataset["rotations"] = np.array(dataset["rotations"], dtype="intc", order="C") dataset["translations"] = np.array( dataset["translations"], dtype="double", order="C", ) dataset["time_reversals"] = ( np.array(dataset["time_reversals"], dtype="intc", order="C") == 1 ) dataset["equivalent_atoms"] = np.array(dataset["equivalent_atoms"], dtype="intc") dataset["transformation_matrix"] = np.array( dataset["transformation_matrix"], dtype="double", order="C", ) dataset["origin_shift"] = np.array(dataset["origin_shift"], dtype="double") dataset["std_lattice"] = np.array( np.transpose(dataset["std_lattice"]), dtype="double", order="C", ) dataset["std_types"] = np.array(dataset["std_types"], dtype="intc") dataset["std_positions"] = np.array( dataset["std_positions"], dtype="double", order="C", ) dataset["std_rotation_matrix"] = np.array( dataset["std_rotation_matrix"], dtype="double", order="C", ) dataset["primitive_lattice"] = np.array( np.transpose(dataset["primitive_lattice"]), dtype="double", order="C", ) dataset["std_tensors"] = np.array(dataset["std_tensors"], dtype="double", order="C") if tensor_rank == 1: dataset["std_tensors"] = dataset["std_tensors"].reshape(-1, 3) return dataset
[docs] def get_layergroup(cell: Cell, aperiodic_dir=2, symprec=1e-5): """Return layer group in .... If it fails, None is returned. """ _set_no_error() dataset = get_symmetry_layerdataset( cell, aperiodic_dir=aperiodic_dir, symprec=symprec, ) return dataset
[docs] def get_spacegroup( cell: Cell, symprec=1e-5, angle_tolerance=-1.0, symbol_type=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. If it fails, None is returned. """ _set_no_error() dataset = get_symmetry_dataset( cell, symprec=symprec, angle_tolerance=angle_tolerance, ) if dataset is None: _set_error_message() return None spg_type = get_spacegroup_type(dataset["hall_number"]) if symbol_type == 1: return "%s (%d)" % (spg_type["schoenflies"], dataset["number"]) else: return "%s (%d)" % (spg_type["international_short"], dataset["number"])
[docs] def get_spacegroup_type(hall_number: int) -> 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`. Parameters ---------- hall_number : int Hall symbol ID. Returns ------- spacegroup_type: SpaceGroupType or None Notes ----- .. versionadded:: 1.9.4 .. versionchanged:: 2.0 ``hall_number`` member is added. """ _set_no_error() spg_type_list = _spglib.spacegroup_type(hall_number) if spg_type_list is not None: spg_type = SpaceGroupType( number=spg_type_list[0], international_short=spg_type_list[1].strip(), international_full=spg_type_list[2].strip(), international=spg_type_list[3].strip(), schoenflies=spg_type_list[4].strip(), hall_number=spg_type_list[5], hall_symbol=spg_type_list[6].strip(), choice=spg_type_list[7].strip(), pointgroup_international=spg_type_list[8].strip(), pointgroup_schoenflies=spg_type_list[9].strip(), arithmetic_crystal_class_number=spg_type_list[10], arithmetic_crystal_class_symbol=spg_type_list[11].strip(), ) return spg_type else: _set_error_message() return None
[docs] def get_spacegroup_type_from_symmetry( rotations, translations, lattice=None, symprec=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. The parameter ``lattice`` is used as the distance measure for ``symprec``. If this is not given, the cubic basis vector whose lengths are one is used. 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. This is used as the measure of distance. Default is None, which gives unit matrix. shape=(3, 3), order='C', dtype='double' symprec: float See :func:`get_symmetry`. Returns ------- spacegroup_type : 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(lattice, dtype="double", order="C") _set_no_error() spg_type_list = _spglib.spacegroup_type_from_symmetry(r, t, _lattice, symprec) if spg_type_list is not None: spg_type = SpaceGroupType( number=spg_type_list[0], international_short=spg_type_list[1].strip(), international_full=spg_type_list[2].strip(), international=spg_type_list[3].strip(), schoenflies=spg_type_list[4].strip(), hall_number=spg_type_list[5], hall_symbol=spg_type_list[6].strip(), choice=spg_type_list[7].strip(), pointgroup_international=spg_type_list[8].strip(), pointgroup_schoenflies=spg_type_list[9].strip(), arithmetic_crystal_class_number=spg_type_list[10], arithmetic_crystal_class_symbol=spg_type_list[11].strip(), ) return spg_type else: _set_error_message() return None
[docs] def get_magnetic_spacegroup_type(uni_number: int) -> MagneticSpaceGroupType | None: """Translate UNI number to magnetic space group type information. If fails, return None. Parameters ---------- uni_number : int UNI number between 1 to 1651 Returns ------- magnetic_spacegroup_type: MagneticSpaceGroupType Notes ----- .. versionadded:: 2.0 """ _set_no_error() msg_type_list = _spglib.magnetic_spacegroup_type(uni_number) if msg_type_list is not None: msg_type = MagneticSpaceGroupType( uni_number=msg_type_list[0], litvin_number=msg_type_list[1], bns_number=msg_type_list[2].strip(), og_number=msg_type_list[3].strip(), number=msg_type_list[4], type=msg_type_list[5], ) return msg_type else: _set_error_message() return None
[docs] def get_magnetic_spacegroup_type_from_symmetry( rotations: ArrayLike[np.intc], translations: ArrayLike[np.double], time_reversals: ArrayLike[np.intc], lattice: ArrayLike[np.double] | None = None, symprec: float = 1e-5, ) -> MagneticSpaceGroupType | None: """Return magnetic space-group type information from symmetry operations. Parameters ---------- rotations, translations, time_reversals: See returns of :func:`get_magnetic_symmetry`. lattice : (Optional) array_like (3, 3) Basis vectors a, b, c given in row vectors. This is used as the measure of distance. Default is None, which gives unit matrix. symprec: float See :func:`get_symmetry`. Returns ------- magnetic_spacegroup_type: MagneticSpaceGroupType """ rots = np.array(rotations, dtype="intc", order="C") trans = np.array(translations, dtype="double", order="C") timerev = np.array(time_reversals, dtype="intc", order="C") if lattice is None: latt = np.eye(3, dtype="double", order="C") else: latt = np.array(lattice, dtype="double", order="C") _set_no_error() msg_type_list = _spglib.magnetic_spacegroup_type_from_symmetry( rots, trans, timerev, latt, symprec ) if msg_type_list is not None: msg_type = MagneticSpaceGroupType( uni_number=msg_type_list[0], litvin_number=msg_type_list[1], bns_number=msg_type_list[2].strip(), og_number=msg_type_list[3].strip(), number=msg_type_list[4], type=msg_type_list[5], ) return msg_type else: _set_error_message() return None
[docs] def get_pointgroup(rotations) -> tuple[str, int, np.ndarray]: """Return point group in international table symbol and number. The symbols are mapped to the numbers as follows: 1 "1 " 2 "-1 " 3 "2 " 4 "m " 5 "2/m " 6 "222 " 7 "mm2 " 8 "mmm " 9 "4 " 10 "-4 " 11 "4/m " 12 "422 " 13 "4mm " 14 "-42m " 15 "4/mmm" 16 "3 " 17 "-3 " 18 "32 " 19 "3m " 20 "-3m " 21 "6 " 22 "-6 " 23 "6/m " 24 "622 " 25 "6mm " 26 "-62m " 27 "6/mmm" 28 "23 " 29 "m-3 " 30 "432 " 31 "-43m " 32 "m-3m " """ _set_no_error() # (symbol, pointgroup_number, transformation_matrix) pointgroup = _spglib.pointgroup(np.array(rotations, dtype="intc", order="C")) _set_error_message() return pointgroup
[docs] def standardize_cell( cell: Cell, to_primitive=False, no_idealize=False, symprec=1e-5, angle_tolerance=-1.0, ): """Return standardized cell. When the search failed, ``None`` is returned. Parameters ---------- cell, symprec, angle_tolerance: See the docstring of get_symmetry. to_primitive : bool If True, the standardized primitive cell is created. no_idealize : bool If True, it is disabled to idealize lengths and angles of basis vectors and positions of atoms according to crystal symmetry. Returns ------- The standardized unit cell or primitive cell is returned by a tuple of (lattice, positions, numbers). If it fails, None is returned. Notes ----- .. versionadded:: 1.8 Now :func:`refine_cell` and :func:`find_primitive` are shorthands of this method with combinations of these options. About the default choice of the setting, see the documentation of ``hall_number`` argument of :func:`get_symmetry_dataset`. More detailed explanation is shown in the spglib (C-API) document. """ _set_no_error() lattice, _positions, _numbers, _ = _expand_cell(cell) # Atomic positions have to be specified by scaled positions for spglib. num_atom = len(_positions) positions = np.zeros((num_atom * 4, 3), dtype="double", order="C") positions[:num_atom] = _positions numbers = np.zeros(num_atom * 4, dtype="intc") numbers[:num_atom] = _numbers num_atom_std = _spglib.standardize_cell( lattice, positions, numbers, num_atom, to_primitive * 1, no_idealize * 1, symprec, angle_tolerance, ) if num_atom_std > 0: return ( np.array(lattice.T, dtype="double", order="C"), np.array(positions[:num_atom_std], dtype="double", order="C"), np.array(numbers[:num_atom_std], dtype="intc"), ) else: _set_error_message() return None
[docs] def refine_cell(cell: Cell, symprec=1e-5, angle_tolerance=-1.0): """Return refined cell. When the search failed, ``None`` is returned. The standardized unit cell is returned by a tuple of (lattice, positions, numbers). Notes ----- .. versionchanged:: 1.8 The detailed control of standardization of unit cell can be done using :func:`standardize_cell`. """ _set_no_error() lattice, _positions, _numbers, _ = _expand_cell(cell) # Atomic positions have to be specified by scaled positions for spglib. num_atom = len(_positions) positions = np.zeros((num_atom * 4, 3), dtype="double", order="C") positions[:num_atom] = _positions numbers = np.zeros(num_atom * 4, dtype="intc") numbers[:num_atom] = _numbers num_atom_std = _spglib.refine_cell( lattice, positions, numbers, num_atom, symprec, angle_tolerance, ) if num_atom_std > 0: return ( np.array(lattice.T, dtype="double", order="C"), np.array(positions[:num_atom_std], dtype="double", order="C"), np.array(numbers[:num_atom_std], dtype="intc"), ) else: _set_error_message() return None
[docs] def find_primitive(cell: Cell, symprec=1e-5, angle_tolerance=-1.0): """Primitive cell is searched in the input cell. If it fails, ``None`` is returned. The primitive cell is returned by a tuple of (lattice, positions, numbers). Notes ----- .. versionchanged:: 1.8 The detailed control of standardization of unit cell can be done using :func:`standardize_cell`. """ _set_no_error() lattice, positions, numbers, _ = _expand_cell(cell) num_atom_prim = _spglib.primitive( lattice, positions, numbers, symprec, angle_tolerance ) if num_atom_prim > 0: return ( np.array(lattice.T, dtype="double", order="C"), np.array(positions[:num_atom_prim], dtype="double", order="C"), np.array(numbers[:num_atom_prim], dtype="intc"), ) else: _set_error_message() return None
[docs] def get_symmetry_from_database(hall_number) -> dict | 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") num_sym = _spglib.symmetry_from_database(rotations, translations, hall_number) if num_sym is None: _set_error_message() return None else: return { "rotations": np.array(rotations[:num_sym], dtype="intc", order="C"), "translations": np.array(translations[:num_sym], dtype="double", order="C"), }
[docs] def get_magnetic_symmetry_from_database(uni_number, hall_number=0) -> dict | None: """Return magnetic symmetry operations from UNI number between 1 and 1651. If fails, return None. Optionally alternative settings can be specified with Hall number. Parameters ---------- uni_number : int UNI number between 1 and 1651. hall_number : int, optional The Hall symbol is given by the serial number in between 1 and 530. Returns ------- symmetry : dict - 'rotations' - 'translations' - 'time_reversals' 0 and 1 indicate ordinary and anti-time-reversal operations, respectively. Notes ----- .. versionadded:: 2.0 """ _set_no_error() rotations = np.zeros((384, 3, 3), dtype="intc") translations = np.zeros((384, 3), dtype="double") time_reversals = np.zeros(384, dtype="intc") num_sym = _spglib.magnetic_symmetry_from_database( rotations, translations, time_reversals, uni_number, hall_number, ) if num_sym is None: _set_error_message() return None else: return { "rotations": np.array(rotations[:num_sym], dtype="intc", order="C"), "translations": np.array(translations[:num_sym], dtype="double", order="C"), "time_reversals": np.array( time_reversals[:num_sym], dtype="intc", order="C", ), }
############ # k-points # ############
[docs] def get_grid_point_from_address(grid_address, mesh): """Return grid point index by translating grid address.""" _set_no_error() return _spglib.grid_point_from_address( np.array(grid_address, dtype="intc"), np.array(mesh, dtype="intc"), )
[docs] def get_ir_reciprocal_mesh( mesh, cell, is_shift=None, is_time_reversal=True, symprec=1e-5, is_dense=False, ): """Return k-points mesh and k-point map to the irreducible k-points. The symmetry is searched from the input cell. Parameters ---------- mesh : array_like Uniform sampling mesh numbers. dtype='intc', shape=(3,) cell : spglib cell tuple Crystal structure. is_shift : array_like, optional [0, 0, 0] gives Gamma center mesh and value 1 gives half mesh shift. Default is None which equals to [0, 0, 0]. dtype='intc', shape=(3,) is_time_reversal : bool, optional Whether time reversal symmetry is included or not. Default is True. symprec : float, optional Symmetry tolerance in distance. Default is 1e-5. is_dense : bool, optional grid_mapping_table is returned with dtype='uintp' if True. Otherwise its dtype='intc'. Default is False. Returns ------- grid_mapping_table : ndarray Grid point mapping table to ir-gird-points. dtype='intc' or 'uintp', shape=(prod(mesh),) grid_address : ndarray Address of all grid points. dtype='intc', shape=(prod(mesh), 3) """ _set_no_error() lattice, positions, numbers, _ = _expand_cell(cell) if lattice is None: return None if is_dense: dtype = "uintp" else: dtype = "intc" grid_mapping_table = np.zeros(np.prod(mesh), dtype=dtype) grid_address = np.zeros((np.prod(mesh), 3), dtype="intc") if is_shift is None: is_shift = [0, 0, 0] if ( _spglib.ir_reciprocal_mesh( grid_address, grid_mapping_table, np.array(mesh, dtype="intc"), np.array(is_shift, dtype="intc"), is_time_reversal * 1, lattice, positions, numbers, symprec, ) > 0 ): return grid_mapping_table, grid_address else: _set_error_message() return None
[docs] def get_stabilized_reciprocal_mesh( mesh, rotations, is_shift=None, is_time_reversal=True, qpoints=None, is_dense=False, ): """Return k-point map to the irreducible k-points and k-point grid points. The symmetry is searched from the input rotation matrices in real space. Parameters ---------- mesh : array_like Uniform sampling mesh numbers. dtype='intc', shape=(3,) rotations : array_like Rotation matrices with respect to real space basis vectors. dtype='intc', shape=(rotations, 3) is_shift : array_like [0, 0, 0] gives Gamma center mesh and value 1 gives half mesh shift. dtype='intc', shape=(3,) is_time_reversal : bool Time reversal symmetry is included or not. qpoints : array_like q-points used as stabilizer(s) given in reciprocal space with respect to reciprocal basis vectors. dtype='double', shape=(qpoints ,3) or (3,) is_dense : bool, optional grid_mapping_table is returned with dtype='uintp' if True. Otherwise its dtype='intc'. Default is False. Returns ------- grid_mapping_table : ndarray Grid point mapping table to ir-gird-points. dtype='intc', shape=(prod(mesh),) grid_address : ndarray Address of all grid points. Each address is given by three unsigned integers. dtype='intc', shape=(prod(mesh), 3) """ _set_no_error() if is_dense: dtype = "uintp" else: dtype = "intc" mapping_table = np.zeros(np.prod(mesh), dtype=dtype) grid_address = np.zeros((np.prod(mesh), 3), dtype="intc") if is_shift is None: is_shift = [0, 0, 0] if qpoints is None: qpoints = np.array([[0, 0, 0]], dtype="double", order="C") else: qpoints = np.array(qpoints, dtype="double", order="C") if qpoints.shape == (3,): qpoints = np.array([qpoints], dtype="double", order="C") if ( _spglib.stabilized_reciprocal_mesh( grid_address, mapping_table, np.array(mesh, dtype="intc"), np.array(is_shift, dtype="intc"), is_time_reversal * 1, np.array(rotations, dtype="intc", order="C"), qpoints, ) > 0 ): return mapping_table, grid_address else: _set_error_message() return None
[docs] def get_grid_points_by_rotations( address_orig, reciprocal_rotations, mesh, is_shift=None, is_dense=False, ): """Return grid points obtained after rotating input grid address. Parameters ---------- address_orig : array_like Grid point address to be rotated. dtype='intc', shape=(3,) reciprocal_rotations : array_like Rotation matrices {R} with respect to reciprocal basis vectors. Defined by q'=Rq. dtype='intc', shape=(rotations, 3, 3) mesh : array_like dtype='intc', shape=(3,) is_shift : array_like, optional With (1) or without (0) half grid shifts with respect to grid intervals sampled along reciprocal basis vectors. Default is None, which gives [0, 0, 0]. is_dense : bool, optional rot_grid_points is returned with dtype='uintp' if True. Otherwise its dtype='intc'. Default is False. Returns ------- rot_grid_points : ndarray Grid points obtained after rotating input grid address dtype='intc' or 'uintp', shape=(rotations,) """ _set_no_error() if is_shift is None: _is_shift = np.zeros(3, dtype="intc") else: _is_shift = np.array(is_shift, dtype="intc") rot_grid_points = np.zeros(len(reciprocal_rotations), dtype="uintp") _spglib.grid_points_by_rotations( rot_grid_points, np.array(address_orig, dtype="intc"), np.array(reciprocal_rotations, dtype="intc", order="C"), np.array(mesh, dtype="intc"), _is_shift, ) if is_dense: return rot_grid_points else: return np.array(rot_grid_points, dtype="intc")
[docs] def get_BZ_grid_points_by_rotations( address_orig, reciprocal_rotations, mesh, bz_map, is_shift=None, is_dense=False, ): """Return grid points obtained after rotating input grid address. Parameters ---------- address_orig : array_like Grid point address to be rotated. dtype='intc', shape=(3,) reciprocal_rotations : array_like Rotation matrices {R} with respect to reciprocal basis vectors. Defined by q'=Rq. dtype='intc', shape=(rotations, 3, 3) mesh : array_like dtype='intc', shape=(3,) bz_map : array_like TODO is_shift : array_like, optional With (1) or without (0) half grid shifts with respect to grid intervals sampled along reciprocal basis vectors. Default is None, which gives [0, 0, 0]. is_dense : bool, optional rot_grid_points is returned with dtype='uintp' if True. Otherwise its dtype='intc'. Default is False. Returns ------- rot_grid_points : ndarray Grid points obtained after rotating input grid address dtype='intc' or 'uintp', shape=(rotations,) """ _set_no_error() if is_shift is None: _is_shift = np.zeros(3, dtype="intc") else: _is_shift = np.array(is_shift, dtype="intc") if bz_map.dtype == "uintp" and bz_map.flags.c_contiguous: _bz_map = bz_map else: _bz_map = np.array(bz_map, dtype="uintp") rot_grid_points = np.zeros(len(reciprocal_rotations), dtype="uintp") _spglib.BZ_grid_points_by_rotations( rot_grid_points, np.array(address_orig, dtype="intc"), np.array(reciprocal_rotations, dtype="intc", order="C"), np.array(mesh, dtype="intc"), _is_shift, _bz_map, ) if is_dense: return rot_grid_points else: return np.array(rot_grid_points, dtype="intc")
[docs] def relocate_BZ_grid_address( grid_address, mesh, reciprocal_lattice, # column vectors is_shift=None, is_dense=False, ): """Grid addresses are relocated to be inside first Brillouin zone. Number of ir-grid-points inside Brillouin zone is returned. It is assumed that the following arrays have the shapes of bz_grid_address : (num_grid_points_in_FBZ, 3) bz_map (prod(mesh * 2), ) Note that the shape of grid_address is (prod(mesh), 3) and the addresses in grid_address are arranged to be in parallelepiped made of reciprocal basis vectors. The addresses in bz_grid_address are inside the first Brillouin zone or on its surface. Each address in grid_address is mapped to one of those in bz_grid_address by a reciprocal lattice vector (including zero vector) with keeping element order. For those inside first Brillouin zone, the mapping is one-to-one. For those on the first Brillouin zone surface, more than one addresses in bz_grid_address that are equivalent by the reciprocal lattice translations are mapped to one address in grid_address. In this case, those grid points except for one of them are appended to the tail of this array, for which bz_grid_address has the following data storing: .. code-block:: |------------------array size of bz_grid_address-------------------------| |--those equivalent to grid_address--|--those on surface except for one--| |-----array size of grid_address-----| Number of grid points stored in bz_grid_address is returned. bz_map is used to recover grid point index expanded to include BZ surface from grid address. The grid point indices are mapped to (mesh[0] * 2) x (mesh[1] * 2) x (mesh[2] * 2) space (bz_map). """ _set_no_error() if is_shift is None: _is_shift = np.zeros(3, dtype="intc") else: _is_shift = np.array(is_shift, dtype="intc") bz_grid_address = np.zeros((np.prod(np.add(mesh, 1)), 3), dtype="intc") bz_map = np.zeros(np.prod(np.multiply(mesh, 2)), dtype="uintp") num_bz_ir = _spglib.BZ_grid_address( bz_grid_address, bz_map, grid_address, np.array(mesh, dtype="intc"), np.array(reciprocal_lattice, dtype="double", order="C"), _is_shift, ) if is_dense: return bz_grid_address[:num_bz_ir], bz_map else: return bz_grid_address[:num_bz_ir], np.array(bz_map, dtype="intc")
[docs] def delaunay_reduce(lattice, eps=1e-5): r"""Run Delaunay reduction. When the search failed, `None` is returned. The transformation from original basis vectors :math:`( \mathbf{a} \; \mathbf{b} \; \mathbf{c} )` to final basis vectors :math:`( \mathbf{a}' \; \mathbf{b}' \; \mathbf{c}' )` is achieved by linear combination of basis vectors with integer coefficients without rotating coordinates. Therefore the transformation matrix is obtained by :math:`\mathbf{P} = ( \mathbf{a} \; \mathbf{b} \; \mathbf{c} ) ( \mathbf{a}' \; \mathbf{b}' \; \mathbf{c}' )^{-1}` and the matrix elements have to be almost integers. The algorithm is found in the international tables for crystallography volume A. Parameters ---------- lattice: ndarray, (3, 3) Lattice parameters in the form of .. code-block:: [[a_x, a_y, a_z], [b_x, b_y, b_z], [c_x, c_y, c_z]] eps: float Tolerance parameter, but unlike `symprec` the unit is not a length. Tolerance to check if volume is close to zero or not and if two basis vectors are orthogonal by the value of dot product being close to zero or not. Returns ------- delaunay_lattice: ndarray, (3, 3) Reduced lattice parameters are given as a numpy 'double' array: .. code-block:: [[a_x, a_y, a_z], [b_x, b_y, b_z], [c_x, c_y, c_z]] Notes ----- .. versionadded:: 1.9.4 """ # noqa: E501 _set_no_error() delaunay_lattice = np.array(np.transpose(lattice), dtype="double", order="C") result = _spglib.delaunay_reduce(delaunay_lattice, float(eps)) if result == 0: _set_error_message() return None else: return np.array(np.transpose(delaunay_lattice), dtype="double", order="C")
[docs] def niggli_reduce(lattice, eps=1e-5): r"""Run Niggli reduction. When the search failed, ``None`` is returned. The transformation from original basis vectors :math:`( \mathbf{a} \; \mathbf{b} \; \mathbf{c} )` to final basis vectors :math:`( \mathbf{a}' \; \mathbf{b}' \; \mathbf{c}' )` is achieved by linear combination of basis vectors with integer coefficients without rotating coordinates. Therefore the transformation matrix is obtained by :math:`\mathbf{P} = ( \mathbf{a} \; \mathbf{b} \; \mathbf{c} ) ( \mathbf{a}' \; \mathbf{b}' \; \mathbf{c}' )^{-1}` and the matrix elements have to be almost integers. The algorithm detail is found at https://atztogo.github.io/niggli/ and the references are there in. Parameters ---------- lattice: ndarray Lattice parameters in the form of .. code-block:: [[a_x, a_y, a_z], [b_x, b_y, b_z], [c_x, c_y, c_z]] eps: float Tolerance parameter, but unlike `symprec` the unit is not a length. This is used to check if difference of norms of two basis vectors is close to zero or not and if two basis vectors are orthogonal by the value of dot product being close to zero or not. The detail is shown at https://atztogo.github.io/niggli/. Returns ------- niggli_lattice: ndarray, (3, 3) if the Niggli reduction succeeded: Reduced lattice parameters are given as a numpy 'double' array: .. code-block:: [[a_x, a_y, a_z], [b_x, b_y, b_z], [c_x, c_y, c_z]] otherwise None is returned. Notes ----- .. versionadded:: 1.9.4 """ # noqa: E501 _set_no_error() niggli_lattice = np.array(np.transpose(lattice), dtype="double", order="C") result = _spglib.niggli_reduce(niggli_lattice, float(eps)) if result == 0: _set_error_message() return None else: return np.array(np.transpose(niggli_lattice), dtype="double", order="C")
[docs] def get_error_message(): """Return error message why spglib failed. .. warning:: This method is not thread safe, i.e., only safely usable when calling one spglib method per process. Notes ----- .. versionadded:: 1.9.5 """ return spglib_error.message
def _expand_cell( cell: Cell, ) -> tuple[np.ndarray, np.ndarray, np.ndarray, np.ndarray | None]: lattice = np.array(np.transpose(cell[0]), dtype="double", order="C") positions = np.array(cell[1], dtype="double", order="C") numbers = np.array(cell[2], dtype="intc") if len(cell) == 4: magmoms = np.array(cell[3], order="C", dtype="double") elif len(cell) == 3: magmoms = None else: raise TypeError("cell has to be a tuple of 3 or 4 elements.") # Sanity check if lattice.shape != (3, 3): raise TypeError("lattice has to be a (3, 3) array.") if not (positions.ndim == 2 and positions.shape[1] == 3): raise TypeError("positions has to be a (num_atoms, 3) array.") num_atoms = positions.shape[0] if numbers.ndim != 1: raise TypeError("numbers has to be a (num_atoms,) array.") if len(numbers) != num_atoms: raise TypeError("numbers has to have the same number of atoms as positions.") if magmoms is not None: if len(magmoms) != num_atoms: raise TypeError( "magmoms has to have the same number of atoms as positions." ) if magmoms.ndim == 1: # collinear pass elif magmoms.ndim == 2: # non-collinear if magmoms.shape[1] != 3: raise TypeError( "non-collinear magmoms has to be a (num_atoms, 3) array." ) else: raise TypeError("magmoms has to be a 1D or 2D array.") return (lattice, positions, numbers, magmoms) def _set_error_message(): spglib_error.message = _spglib.error_message() def _set_no_error(): spglib_error.message = "no error"
[docs] def get_hall_number_from_symmetry(rotations, translations, symprec=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``. """ warnings.warn( "get_hall_number_from_symmetry() is deprecated. " "Use get_spacegroup_type_from_symmetry() instead.", DeprecationWarning, ) r = np.array(rotations, dtype="intc", order="C") t = np.array(translations, dtype="double", order="C") hall_number = _spglib.hall_number_from_symmetry(r, t, symprec) return hall_number