# MAGNOPY - Python package for magnons.
# Copyright (C) 2023-2025 Magnopy Team
#
# e-mail: anry@uv.es, web: magnopy.com
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
import os
import numpy as np
from wulfric.cell import get_params
from wulfric.crystal import get_atom_species
from magnopy._constants._internal_units import ENERGY
from magnopy._package_info import logo
from magnopy._parameters._p22 import to_dmi, to_symm_anisotropy
from magnopy._spinham._convention import Convention
from magnopy._spinham._hamiltonian import SpinHamiltonian
# Save local scope at this moment
old_dir = set(dir())
old_dir.add("old_dir")
[docs]
def dump_vampire(
spinham: SpinHamiltonian,
seedname="vampire",
anisotropic=True,
dmi=True,
custom_mask=None,
decimals=5,
materials=None,
no_logo=False,
):
"""
Save the Hamiltonian in the format suitable for |Vampire|_.
Parameters
----------
spinham : :py:class:`.SpinHamiltonian`
Spin Hamiltonian to be saved.
seedname : str, default "vampire"
Seedname for the .UCF and .mat files. Extensions are added automatically.
Input file always have the name "input".
anisotropic : bool, default True
Whether to output anisotropic exchange.
dmi : bool, default True
Whether to output DMI exchange.
custom_mask : func, optional
Custom mask for the exchange parameter. Function which take (3,3) numpy:`ndarray`
as an input and returns (3,3) numpy:`ndarray` as an output. If given, then
``anisotropic`` and ``dmi`` parameters are ignored.
decimals : int, default 4
Number of decimals to be printed (only for the exchange values).
materials : list of int, optional
List of materials for the atoms. Has to have the same length as the number of
magnetic atoms in the ``spinham``. Order is the same as in :py:attr:`.SpinHamiltonian.magnetic_atoms`.
If not given, each atom will be considered as a separate material. Starting from 0.
no_logo : bool, default False
Whether to print the logo in the output files.
Returns
-------
content : str
Content of the .UCF file if ``filename`` is not given.
"""
head, _ = os.path.split(seedname)
if head != "":
os.makedirs(head, exist_ok=True)
dump_vampire_ucf(
spinham,
filename=seedname + ".UCF",
anisotropic=anisotropic,
dmi=dmi,
custom_mask=custom_mask,
decimals=decimals,
materials=materials,
no_logo=no_logo,
)
dump_vampire_mat(
spinham,
filename=seedname + ".mat",
materials=materials,
no_logo=no_logo,
)
with open(os.path.join(head, "input-template"), "w", encoding="utf-8") as file:
if not no_logo:
file.write(logo(comment=True, date_time=True) + "\n")
file.write(
"\n".join(
[
"#------------------------------------------",
f"material:file={seedname}.mat",
f"material:unit-cell-file = {seedname}.UCF",
"#------------------------------------------",
"# TODO: your simulation parameters",
]
)
)
[docs]
def dump_vampire_mat(
spinham: SpinHamiltonian, filename=None, materials=None, no_logo=False
):
"""
Write .mat file for |Vampire|_.
Parameters
----------
spinham : :py:class:`.SpinHamiltonian`
Spin Hamiltonian to be saved.
filename : str, optional
Name for the .mat file. No extensions is added automatically.
If not given, the output is returned as a string.
materials : list of int, optional
List of materials for the atoms. Has to have the same length as the number of
magnetic atoms in the ``spinham``. If not given, each atom will be considered
as a separate material. Material index starts from 0 and should contain all
consecutive integers between 0 and number of materials. Number of materials
cannot be higher than number of magnetic atoms.
no_logo : bool, default False
Whether to print the logo in the output files.
Notes
-----
Examples of the correct ``materials`` list for 5 magnetic atoms
.. code-block:: python
[0, 0, 0, 0, 0]
[1, 3, 2, 1, 0]
[0, 1, 2, 3, 4]
"""
if materials is None:
materials = [i for i in range(len(spinham.magnetic_atoms.names))]
else:
if len(materials) != len(spinham.magnetic_atoms.names):
raise ValueError(
f"Expected {len(spinham.magnetic_atoms.names)} materials, got "
f"{len(materials)}."
)
materials_pool = set(materials)
higher_material = max(materials_pool)
for i in range(0, higher_material + 1):
if i not in materials_pool:
raise ValueError(
f"Materials indices should be consecutive integers between 0 and "
f"{higher_material}. Missing {i}."
)
if no_logo:
text = []
else:
text = [logo(comment=True, date_time=True)]
text.append(f"material:num-materials = {max(materials)+1}")
for i in range(spinham.M):
if materials[i] not in materials[:i]:
m_i = materials[i] + 1
text.append("#---------------------------------------------------")
text.append(f"# Material {m_i} \n")
text.append("#---------------------------------------------------")
text.append(
f"material[{m_i}]:material-name = {spinham.magnetic_atoms.names[i]}"
)
text.append(
f"material[{m_i}]:material-element = {get_atom_species(spinham.magnetic_atoms.names[i])}"
)
text.append(
f"material[{m_i}]:atomic-spin-moment={spinham.magnetic_atoms.spins[i]*spinham.magnetic_atoms.g_factors[i]} ! muB"
)
text.append(f"material[{m_i}]:initial-spin-direction = random")
text.append(f"material[{m_i}]:damping-constant = 0.1")
text.append(f"material[{m_i}]:uniaxial-anisotropy-constant = 0.0")
text.append("#---------------------------------------------------")
text = "\n".join(text)
if filename is None:
return "".join(text)
with open(filename, "w", encoding="utf-8") as file:
file.write("".join(text))
[docs]
def dump_vampire_ucf(
spinham: SpinHamiltonian,
filename=None,
anisotropic=True,
dmi=True,
custom_mask=None,
decimals=5,
materials=None,
no_logo=False,
):
"""
Write .UCF file for |Vampire|_.
Parameters
----------
spinham : :py:class:`.SpinHamiltonian`
Spin Hamiltonian to be saved.
filename : str, optional
Name for the .UCF file. No extension is added automatically.
If not given, the output is returned as a string.
anisotropic : bool, default True
Whether to output anisotropic exchange.
dmi : bool, default True
Whether to output DMI exchange.
custom_mask : func, optional
Custom mask for the exchange parameter. Function which take (3,3) numpy:`ndarray`
as an input and returns (3,3) numpy:`ndarray` as an output. If given, then
``anisotropic`` and ``dmi`` parameters are ignored.
decimals : int, default 4
Number of decimals to be printed (only for the exchange values).
materials : list of int, optional
List of materials for the atoms. Has to have the same length as the number of
magnetic atoms in the ``spinham``. Order is the same as in :py:attr:`.SpinHamiltonian.magnetic_atoms`.
If not given, each atom will be considered as a separate material.
no_logo : bool, default False
Whether to print the logo in the output files.
Returns
-------
content : str
Content of the .UCF file if ``filename`` is not given.
"""
if materials is None:
materials = [i for i in range(len(spinham.magnetic_atoms.names))]
original_convention = spinham.convention
spinham.convention = Convention.get_predefined(name="Vampire")
if no_logo:
text = []
else:
text = [logo(comment=True, date_time=True)]
a, b, c, _, _, _ = get_params(spinham.cell)
text.append("# Unit cell size:")
text.append(f"{a:.8f} {b:.8f} {c:.8f}")
text.append("# Unit cell lattice vectors:")
text.append(
f"{spinham.cell[0][0]:15.8f} {spinham.cell[0][1]:15.8f} {spinham.cell[0][2]:15.8f}"
)
text.append(
f"{spinham.cell[1][0]:15.8f} {spinham.cell[1][1]:15.8f} {spinham.cell[1][2]:15.8f}"
)
text.append(
f"{spinham.cell[2][0]:15.8f} {spinham.cell[2][1]:15.8f} {spinham.cell[2][2]:15.8f}"
)
text.append("# Atoms")
text.append(f"{len(spinham.magnetic_atoms.names)} {len(np.unique(materials))}")
for alpha in range(spinham.M):
position = spinham.magnetic_atoms.positions[alpha]
text.append(
f"{alpha:<5} {position[0]:15.8f} {position[1]:15.8f} {position[2]:15.8f} {materials[0]:>5}"
)
text.append("# Interactions")
text.append(f"{len(spinham.p22)} tensorial")
IID = 0
fmt = f"{7+decimals}.{decimals}e"
# Write (two spins & one site)
for alpha, J in spinham.p21:
alpha = spinham.map_to_magnetic[alpha]
if custom_mask is not None:
J = custom_mask(J)
else:
if not dmi:
J -= to_dmi(J, matrix_form=True)
if not anisotropic:
J -= to_symm_anisotropy(J)
J = J * ENERGY
text.append(
f"{IID:<5} {alpha:>3} {alpha:>3} {0:>2} {0:>2} {0:>2} "
f"{J[0][0]:{fmt}} {J[0][1]:{fmt}} {J[0][2]:{fmt}} "
f"{J[1][0]:{fmt}} {J[1][1]:{fmt}} {J[1][2]:{fmt}} "
f"{J[2][0]:{fmt}} {J[2][1]:{fmt}} {J[2][2]:{fmt}}"
)
IID += 1
# Write (two spins & two sites)
bonds = []
for alpha, beta, nu, J in spinham.p22:
alpha = spinham.map_to_magnetic[alpha]
beta = spinham.map_to_magnetic[beta]
if custom_mask is not None:
J = custom_mask(J)
else:
if not dmi:
J -= to_dmi(J, matrix_form=True)
if not anisotropic:
J -= to_symm_anisotropy(J)
# print(alpha, beta, nu)
# print(J, end="\n\n")
J = J * ENERGY
r_alpha = np.array(spinham.magnetic_atoms.positions[alpha])
r_beta = np.array(spinham.magnetic_atoms.positions[beta])
distance = np.linalg.norm((r_beta - r_alpha + nu) @ spinham.cell)
bonds.append([alpha, beta, nu, J, distance])
bonds = sorted(bonds, key=lambda x: x[4])
for alpha, beta, (i, j, k), J, _ in bonds:
text.append(
f"{IID:<5} {alpha:>3} {beta:>3} {i:>2} {j:>2} {k:>2} "
f"{J[0][0]:{fmt}} {J[0][1]:{fmt}} {J[0][2]:{fmt}} "
f"{J[1][0]:{fmt}} {J[1][1]:{fmt}} {J[1][2]:{fmt}} "
f"{J[2][0]:{fmt}} {J[2][1]:{fmt}} {J[2][2]:{fmt}}"
)
IID += 1
spinham.convention = original_convention
text = "\n".join(text)
if filename is None:
return text
with open(filename, "w", encoding="utf-8") as file:
file.write(text)
# Populate __all__ with objects defined in this file
__all__ = list(set(dir()) - old_dir)
# Remove all semi-private objects
__all__ = [i for i in __all__ if not i.startswith("_")]
del old_dir