# Copyright (C) 2008 CSC - Scientific Computing Ltd.
"""This module defines an ASE interface to VASP.
Developed on the basis of modules by Jussi Enkovaara and John
Kitchin. The path of the directory containing the pseudopotential
directories (potpaw,potpaw_GGA, potpaw_PBE, ...) should be set
by the environmental flag $VASP_PP_PATH.
The user should also set the environmental flag $VASP_SCRIPT pointing
to a python script looking something like::
import os
exitcode = os.system('vasp')
Alternatively, user can set the environmental flag $VASP_COMMAND pointing
to the command use the launch vasp e.g. 'vasp' or 'mpirun -n 16 vasp'
http://cms.mpi.univie.ac.at/vasp/
"""
import os
import re
import subprocess
import sys
from contextlib import contextmanager
from pathlib import Path
from typing import Any, Dict, List, Tuple
from warnings import warn
from xml.etree import ElementTree
import numpy as np
import ase
from ase.calculators import calculator
from ase.calculators.calculator import Calculator
from ase.calculators.singlepoint import SinglePointDFTCalculator
from ase.calculators.vasp.create_input import GenerateVaspInput
from ase.config import cfg
from ase.io import jsonio, read
from ase.utils import PurePath, deprecated
from ase.vibrations.data import VibrationsData
def _prohibit_directory_in_label(args: List, kwargs: Dict[str, Any]) -> bool:
if len(args) >= 5 and "/" in args[4]:
return True
return "/" in kwargs.get("label", "")
[docs]
class Vasp(GenerateVaspInput, Calculator): # type: ignore[misc]
"""ASE interface for the Vienna Ab initio Simulation Package (VASP),
with the Calculator interface.
Parameters:
atoms: object
Attach an atoms object to the calculator.
label: str
Prefix for the output file, and sets the working directory.
Default is 'vasp'.
directory: str
Set the working directory. Is prepended to ``label``.
restart: str or bool
Sets a label for the directory to load files from.
if :code:`restart=True`, the working directory from
``directory`` is used.
txt: bool, None, str or writable object
- If txt is None, output stream will be supressed
- If txt is '-' the output will be sent through stdout
- If txt is a string a file will be opened,\
and the output will be sent to that file.
- Finally, txt can also be a an output stream,\
which has a 'write' attribute.
Default is 'vasp.out'
- Examples:
>>> from ase.calculators.vasp import Vasp
>>> calc = Vasp(label='mylabel', txt='vasp.out') # Redirect stdout
>>> calc = Vasp(txt='myfile.txt') # Redirect stdout
>>> calc = Vasp(txt='-') # Print vasp output to stdout
>>> calc = Vasp(txt=None) # Suppress txt output
command: str
Custom instructions on how to execute VASP. Has priority over
environment variables.
"""
name = 'vasp'
ase_objtype = 'vasp_calculator' # For JSON storage
# Environment commands
env_commands = ('ASE_VASP_COMMAND', 'VASP_COMMAND', 'VASP_SCRIPT')
implemented_properties = [
'energy', 'free_energy', 'forces', 'dipole', 'fermi', 'stress',
'magmom', 'magmoms'
]
# Can be used later to set some ASE defaults
default_parameters: Dict[str, Any] = {}
@deprecated(
'Specifying directory in "label" is deprecated, '
'use "directory" instead.',
category=FutureWarning,
callback=_prohibit_directory_in_label,
)
def __init__(self,
atoms=None,
restart=None,
directory='.',
label='vasp',
ignore_bad_restart_file=Calculator._deprecated,
command=None,
txt='vasp.out',
**kwargs):
"""
.. deprecated:: 3.19.2
Specifying directory in ``label`` is deprecated,
use ``directory`` instead.
"""
self._atoms = None
self.results = {}
# Initialize parameter dictionaries
GenerateVaspInput.__init__(self)
self._store_param_state() # Initialize an empty parameter state
# Store calculator from vasprun.xml here - None => uninitialized
self._xml_calc = None
# Set directory and label
self.directory = directory
if "/" in label:
if self.directory != ".":
msg = (
'Directory redundantly specified though directory='
f'"{self.directory}" and label="{label}". Please omit '
'"/" in label.'
)
raise ValueError(msg)
self.label = label
else:
self.prefix = label # The label should only contain the prefix
if isinstance(restart, bool):
restart = self.label if restart is True else None
Calculator.__init__(
self,
restart=restart,
ignore_bad_restart_file=ignore_bad_restart_file,
# We already, manually, created the label
label=self.label,
atoms=atoms,
**kwargs)
self.command = command
self._txt = None
self.txt = txt # Set the output txt stream
self.version = None
# XXX: This seems to break restarting, unless we return first.
# Do we really still need to enfore this?
# # If no XC combination, GGA functional or POTCAR type is specified,
# # default to PW91. This is mostly chosen for backwards compatibility.
# if kwargs.get('xc', None):
# pass
# elif not (kwargs.get('gga', None) or kwargs.get('pp', None)):
# self.input_params.update({'xc': 'PW91'})
# # A null value of xc is permitted; custom recipes can be
# # used by explicitly setting the pseudopotential set and
# # INCAR keys
# else:
# self.input_params.update({'xc': None})
def make_command(self, command=None):
"""Return command if one is passed, otherwise try to find
ASE_VASP_COMMAND, VASP_COMMAND or VASP_SCRIPT.
If none are set, a CalculatorSetupError is raised"""
if command:
cmd = command
else:
# Search for the environment commands
for env in self.env_commands:
if env in cfg:
cmd = cfg[env].replace('PREFIX', self.prefix)
if env == 'VASP_SCRIPT':
# Make the system python exe run $VASP_SCRIPT
exe = sys.executable
cmd = ' '.join([exe, cmd])
break
else:
msg = ('Please set either command in calculator'
' or one of the following environment '
'variables (prioritized as follows): {}').format(
', '.join(self.env_commands))
raise calculator.CalculatorSetupError(msg)
return cmd
def set(self, **kwargs):
"""Override the set function, to test for changes in the
Vasp Calculator, then call the create_input.set()
on remaining inputs for VASP specific keys.
Allows for setting ``label``, ``directory`` and ``txt``
without resetting the results in the calculator.
"""
changed_parameters = {}
if 'label' in kwargs:
self.label = kwargs.pop('label')
if 'directory' in kwargs:
# str() call to deal with pathlib objects
self.directory = str(kwargs.pop('directory'))
if 'txt' in kwargs:
self.txt = kwargs.pop('txt')
if 'atoms' in kwargs:
atoms = kwargs.pop('atoms')
self.atoms = atoms # Resets results
if 'command' in kwargs:
self.command = kwargs.pop('command')
changed_parameters.update(Calculator.set(self, **kwargs))
# We might at some point add more to changed parameters, or use it
if changed_parameters:
self.clear_results() # We don't want to clear atoms
if kwargs:
# If we make any changes to Vasp input, we always reset
GenerateVaspInput.set(self, **kwargs)
self.results.clear()
def reset(self):
self.atoms = None
self.clear_results()
def clear_results(self):
self.results.clear()
self._xml_calc = None
@contextmanager
def _txt_outstream(self):
"""Custom function for opening a text output stream. Uses self.txt
to determine the output stream, and accepts a string or an open
writable object.
If a string is used, a new stream is opened, and automatically closes
the new stream again when exiting.
Examples:
# Pass a string
calc.txt = 'vasp.out'
with calc.txt_outstream() as out:
calc.run(out=out) # Redirects the stdout to 'vasp.out'
# Use an existing stream
mystream = open('vasp.out', 'w')
calc.txt = mystream
with calc.txt_outstream() as out:
calc.run(out=out)
mystream.close()
# Print to stdout
calc.txt = '-'
with calc.txt_outstream() as out:
calc.run(out=out) # output is written to stdout
"""
txt = self.txt
open_and_close = False # Do we open the file?
if txt is None:
# Suppress stdout
out = subprocess.DEVNULL
else:
if isinstance(txt, str):
if txt == '-':
# subprocess.call redirects this to stdout
out = None
else:
# Open the file in the work directory
txt = self._indir(txt)
# We wait with opening the file, until we are inside the
# try/finally
open_and_close = True
elif hasattr(txt, 'write'):
out = txt
else:
raise RuntimeError('txt should either be a string'
'or an I/O stream, got {}'.format(txt))
try:
if open_and_close:
out = open(txt, 'w')
yield out
finally:
if open_and_close:
out.close()
def calculate(self,
atoms=None,
properties=('energy', ),
system_changes=tuple(calculator.all_changes)):
"""Do a VASP calculation in the specified directory.
This will generate the necessary VASP input files, and then
execute VASP. After execution, the energy, forces. etc. are read
from the VASP output files.
"""
Calculator.calculate(self, atoms, properties, system_changes)
# Check for zero-length lattice vectors and PBC
# and that we actually have an Atoms object.
check_atoms(self.atoms)
self.clear_results()
command = self.make_command(self.command)
self.write_input(self.atoms, properties, system_changes)
with self._txt_outstream() as out:
errorcode, stderr = self._run(command=command,
out=out,
directory=self.directory)
if errorcode:
raise calculator.CalculationFailed(
'{} in {} returned an error: {:d} stderr {}'.format(
self.name, Path(self.directory).resolve(), errorcode,
stderr))
# Read results from calculation
self.update_atoms(atoms)
self.read_results()
def _run(self, command=None, out=None, directory=None):
"""Method to explicitly execute VASP"""
if command is None:
command = self.command
if directory is None:
directory = self.directory
result = subprocess.run(command,
shell=True,
cwd=directory,
capture_output=True,
text=True)
if out is not None:
out.write(result.stdout)
return result.returncode, result.stderr
def check_state(self, atoms, tol=1e-15):
"""Check for system changes since last calculation."""
def compare_dict(d1, d2):
"""Helper function to compare dictionaries"""
# Use symmetric difference to find keys which aren't shared
# for python 2.7 compatibility
if set(d1.keys()) ^ set(d2.keys()):
return False
# Check for differences in values
for key, value in d1.items():
if np.any(value != d2[key]):
return False
return True
# First we check for default changes
system_changes = Calculator.check_state(self, atoms, tol=tol)
# We now check if we have made any changes to the input parameters
# XXX: Should we add these parameters to all_changes?
for param_string, old_dict in self.param_state.items():
param_dict = getattr(self, param_string) # Get current param dict
if not compare_dict(param_dict, old_dict):
system_changes.append(param_string)
return system_changes
def _store_param_state(self):
"""Store current parameter state"""
self.param_state = dict(
float_params=self.float_params.copy(),
exp_params=self.exp_params.copy(),
string_params=self.string_params.copy(),
int_params=self.int_params.copy(),
input_params=self.input_params.copy(),
bool_params=self.bool_params.copy(),
list_int_params=self.list_int_params.copy(),
list_bool_params=self.list_bool_params.copy(),
list_float_params=self.list_float_params.copy(),
dict_params=self.dict_params.copy(),
special_params=self.special_params.copy())
[docs]
def asdict(self):
"""Return a dictionary representation of the calculator state.
Does NOT contain information on the ``command``, ``txt`` or
``directory`` keywords.
Contains the following keys:
- ``ase_version``
- ``vasp_version``
- ``inputs``
- ``results``
- ``atoms`` (Only if the calculator has an ``Atoms`` object)
"""
# Get versions
asevers = ase.__version__
vaspvers = self.get_version()
self._store_param_state() # Update param state
# Store input parameters which have been set
inputs = {
key: value
for param_dct in self.param_state.values()
for key, value in param_dct.items() if value is not None
}
dct = {
'ase_version': asevers,
'vasp_version': vaspvers,
# '__ase_objtype__': self.ase_objtype,
'inputs': inputs,
'results': self.results.copy()
}
if self.atoms:
# Encode atoms as dict
from ase.db.row import atoms2dict
dct['atoms'] = atoms2dict(self.atoms)
return dct
[docs]
def fromdict(self, dct):
"""Restore calculator from a :func:`~ase.calculators.vasp.Vasp.asdict`
dictionary.
Parameters:
dct: Dictionary
The dictionary which is used to restore the calculator state.
"""
if 'vasp_version' in dct:
self.version = dct['vasp_version']
if 'inputs' in dct:
self.set(**dct['inputs'])
self._store_param_state()
if 'atoms' in dct:
from ase.db.row import AtomsRow
atoms = AtomsRow(dct['atoms']).toatoms()
self.atoms = atoms
if 'results' in dct:
self.results.update(dct['results'])
[docs]
def write_json(self, filename):
"""Dump calculator state to JSON file.
Parameters:
filename: string
The filename which the JSON file will be stored to.
Prepends the ``directory`` path to the filename.
"""
filename = self._indir(filename)
dct = self.asdict()
jsonio.write_json(filename, dct)
[docs]
def read_json(self, filename):
"""Load Calculator state from an exported JSON Vasp file."""
dct = jsonio.read_json(filename)
self.fromdict(dct)
def write_input(self, atoms, properties=None, system_changes=None):
"""Write VASP inputfiles, INCAR, KPOINTS and POTCAR"""
self.initialize(atoms)
GenerateVaspInput.write_input(self, atoms, directory=self.directory)
def read(self, label=None):
"""Read results from VASP output files.
Files which are read: OUTCAR, CONTCAR and vasprun.xml
Raises ReadError if they are not found"""
if label is None:
label = self.label
Calculator.read(self, label)
# If we restart, self.parameters isn't initialized
if self.parameters is None:
self.parameters = self.get_default_parameters()
# Check for existence of the necessary output files
for f in ['OUTCAR', 'CONTCAR', 'vasprun.xml']:
file = self._indir(f)
if not file.is_file():
raise calculator.ReadError(
f'VASP outputfile {file} was not found')
# Build sorting and resorting lists
self.read_sort()
# Read atoms
self.atoms = self.read_atoms(filename=self._indir('CONTCAR'))
# Read parameters
self.read_incar(filename=self._indir('INCAR'))
self.read_kpoints(filename=self._indir('KPOINTS'))
self.read_potcar(filename=self._indir('POTCAR'))
# Read the results from the calculation
self.read_results()
def _indir(self, filename):
"""Prepend current directory to filename"""
return Path(self.directory) / filename
def read_sort(self):
"""Create the sorting and resorting list from ase-sort.dat.
If the ase-sort.dat file does not exist, the sorting is redone.
"""
sortfile = self._indir('ase-sort.dat')
if os.path.isfile(sortfile):
self.sort = []
self.resort = []
with open(sortfile) as fd:
for line in fd:
sort, resort = line.split()
self.sort.append(int(sort))
self.resort.append(int(resort))
else:
# Redo the sorting
atoms = read(self._indir('CONTCAR'))
self.initialize(atoms)
def read_atoms(self, filename):
"""Read the atoms from file located in the VASP
working directory. Normally called CONTCAR."""
return read(filename)[self.resort]
def update_atoms(self, atoms):
"""Update the atoms object with new positions and cell"""
if (self.int_params['ibrion'] is not None
and self.int_params['nsw'] is not None):
if self.int_params['ibrion'] > -1 and self.int_params['nsw'] > 0:
# Update atomic positions and unit cell with the ones read
# from CONTCAR.
atoms_sorted = read(self._indir('CONTCAR'))
atoms.positions = atoms_sorted[self.resort].positions
atoms.cell = atoms_sorted.cell
self.atoms = atoms # Creates a copy
def read_results(self):
"""Read the results from VASP output files"""
# Temporarily load OUTCAR into memory
outcar = self.load_file('OUTCAR')
# Read the data we can from vasprun.xml
calc_xml = self._read_xml()
xml_results = calc_xml.results
# Fix sorting
xml_results['forces'] = xml_results['forces'][self.resort]
self.results.update(xml_results)
# Parse the outcar, as some properties are not loaded in vasprun.xml
# We want to limit this as much as possible, as reading large OUTCAR's
# is relatively slow
# Removed for now
# self.read_outcar(lines=outcar)
# Update results dict with results from OUTCAR
# which aren't written to the atoms object we read from
# the vasprun.xml file.
self.converged = self.read_convergence(lines=outcar)
self.version = self.read_version()
magmom, magmoms = self.read_mag(lines=outcar)
dipole = self.read_dipole(lines=outcar)
nbands = self.read_nbands(lines=outcar)
self.results.update(
dict(magmom=magmom, magmoms=magmoms, dipole=dipole, nbands=nbands))
# Stress is not always present.
# Prevent calculation from going into a loop
if 'stress' not in self.results:
self.results.update(dict(stress=None))
self._set_old_keywords()
# Store the parameters used for this calculation
self._store_param_state()
def _set_old_keywords(self):
"""Store keywords for backwards compatibility wd VASP calculator"""
self.spinpol = self.get_spin_polarized()
self.energy_free = self.get_potential_energy(force_consistent=True)
self.energy_zero = self.get_potential_energy(force_consistent=False)
self.forces = self.get_forces()
self.fermi = self.get_fermi_level()
self.dipole = self.get_dipole_moment()
# Prevent calculation from going into a loop
self.stress = self.get_property('stress', allow_calculation=False)
self.nbands = self.get_number_of_bands()
# Below defines some functions for faster access to certain common keywords
@property
def kpts(self):
"""Access the kpts from input_params dict"""
return self.input_params['kpts']
@kpts.setter
def kpts(self, kpts):
"""Set kpts in input_params dict"""
self.input_params['kpts'] = kpts
@property
def encut(self):
"""Direct access to the encut parameter"""
return self.float_params['encut']
@encut.setter
def encut(self, encut):
"""Direct access for setting the encut parameter"""
self.set(encut=encut)
@property
def xc(self):
"""Direct access to the xc parameter"""
return self.get_xc_functional()
@xc.setter
def xc(self, xc):
"""Direct access for setting the xc parameter"""
self.set(xc=xc)
@property
def atoms(self):
return self._atoms
@atoms.setter
def atoms(self, atoms):
if atoms is None:
self._atoms = None
self.clear_results()
else:
if self.check_state(atoms):
self.clear_results()
self._atoms = atoms.copy()
def load_file(self, filename):
"""Reads a file in the directory, and returns the lines
Example:
>>> from ase.calculators.vasp import Vasp
>>> calc = Vasp()
>>> outcar = calc.load_file('OUTCAR') # doctest: +SKIP
"""
filename = self._indir(filename)
with open(filename) as fd:
return fd.readlines()
@contextmanager
def load_file_iter(self, filename):
"""Return a file iterator"""
filename = self._indir(filename)
with open(filename) as fd:
yield fd
def read_outcar(self, lines=None):
"""Read results from the OUTCAR file.
Deprecated, see read_results()"""
if not lines:
lines = self.load_file('OUTCAR')
# Spin polarized calculation?
self.spinpol = self.get_spin_polarized()
self.version = self.get_version()
# XXX: Do we want to read all of this again?
self.energy_free, self.energy_zero = self.read_energy(lines=lines)
self.forces = self.read_forces(lines=lines)
self.fermi = self.read_fermi(lines=lines)
self.dipole = self.read_dipole(lines=lines)
self.stress = self.read_stress(lines=lines)
self.nbands = self.read_nbands(lines=lines)
self.read_ldau()
self.magnetic_moment, self.magnetic_moments = self.read_mag(
lines=lines)
def _read_xml(self) -> SinglePointDFTCalculator:
"""Read vasprun.xml, and return the last calculator object.
Returns calculator from the xml file.
Raises a ReadError if the reader is not able to construct a calculator.
"""
file = self._indir('vasprun.xml')
incomplete_msg = (
f'The file "{file}" is incomplete, and no DFT data was available. '
'This is likely due to an incomplete calculation.')
try:
_xml_atoms = read(file, index=-1, format='vasp-xml')
# Silence mypy, we should only ever get a single atoms object
assert isinstance(_xml_atoms, ase.Atoms)
except ElementTree.ParseError as exc:
raise calculator.ReadError(incomplete_msg) from exc
if _xml_atoms is None or _xml_atoms.calc is None:
raise calculator.ReadError(incomplete_msg)
self._xml_calc = _xml_atoms.calc
return self._xml_calc
@property
def _xml_calc(self) -> SinglePointDFTCalculator:
if self.__xml_calc is None:
raise RuntimeError('vasprun.xml data has not yet been loaded. '
'Run read_results() first.')
return self.__xml_calc
@_xml_calc.setter
def _xml_calc(self, value):
self.__xml_calc = value
def get_ibz_k_points(self):
calc = self._xml_calc
return calc.get_ibz_k_points()
def get_kpt(self, kpt=0, spin=0):
calc = self._xml_calc
return calc.get_kpt(kpt=kpt, spin=spin)
def get_eigenvalues(self, kpt=0, spin=0):
calc = self._xml_calc
return calc.get_eigenvalues(kpt=kpt, spin=spin)
def get_fermi_level(self):
calc = self._xml_calc
return calc.get_fermi_level()
def get_homo_lumo(self):
calc = self._xml_calc
return calc.get_homo_lumo()
def get_homo_lumo_by_spin(self, spin=0):
calc = self._xml_calc
return calc.get_homo_lumo_by_spin(spin=spin)
def get_occupation_numbers(self, kpt=0, spin=0):
calc = self._xml_calc
return calc.get_occupation_numbers(kpt, spin)
def get_spin_polarized(self):
calc = self._xml_calc
return calc.get_spin_polarized()
def get_number_of_spins(self):
calc = self._xml_calc
return calc.get_number_of_spins()
def get_number_of_bands(self):
return self.results.get('nbands', None)
def get_number_of_electrons(self, lines=None):
if not lines:
lines = self.load_file('OUTCAR')
nelect = None
for line in lines:
if 'total number of electrons' in line:
nelect = float(line.split('=')[1].split()[0].strip())
break
return nelect
def get_k_point_weights(self):
filename = 'IBZKPT'
return self.read_k_point_weights(filename)
def get_dos(self, spin=None, **kwargs):
"""
The total DOS.
Uses the ASE DOS module, and returns a tuple with
(energies, dos).
"""
from ase.dft.dos import DOS
dos = DOS(self, **kwargs)
e = dos.get_energies()
d = dos.get_dos(spin=spin)
return e, d
def get_version(self):
if self.version is None:
# Try if we can read the version number
self.version = self.read_version()
return self.version
def read_version(self):
"""Get the VASP version number"""
# The version number is the first occurrence, so we can just
# load the OUTCAR, as we will return soon anyway
if not os.path.isfile(self._indir('OUTCAR')):
return None
with self.load_file_iter('OUTCAR') as lines:
for line in lines:
if ' vasp.' in line:
return line[len(' vasp.'):].split()[0]
# We didn't find the version in VASP
return None
def get_number_of_iterations(self):
return self.read_number_of_iterations()
def read_number_of_iterations(self):
niter = None
with self.load_file_iter('OUTCAR') as lines:
for line in lines:
# find the last iteration number
if '- Iteration' in line:
niter = list(map(int, re.findall(r'\d+', line)))[1]
return niter
def read_number_of_ionic_steps(self):
niter = None
with self.load_file_iter('OUTCAR') as lines:
for line in lines:
if '- Iteration' in line:
niter = list(map(int, re.findall(r'\d+', line)))[0]
return niter
def read_stress(self, lines=None):
"""Read stress from OUTCAR.
Depreciated: Use get_stress() instead.
"""
# We don't really need this, as we read this from vasprun.xml
# keeping it around "just in case" for now
if not lines:
lines = self.load_file('OUTCAR')
stress = None
for line in lines:
if ' in kB ' in line:
stress = -np.array([float(a) for a in line.split()[2:]])
stress = stress[[0, 1, 2, 4, 5, 3]] * 1e-1 * ase.units.GPa
return stress
def read_ldau(self, lines=None):
"""Read the LDA+U values from OUTCAR"""
if not lines:
lines = self.load_file('OUTCAR')
ldau_luj = None
ldauprint = None
ldau = None
ldautype = None
atomtypes = []
# read ldau parameters from outcar
for line in lines:
if line.find('TITEL') != -1: # What atoms are present
atomtypes.append(line.split()[3].split('_')[0].split('.')[0])
if line.find('LDAUTYPE') != -1: # Is this a DFT+U calculation
ldautype = int(line.split('=')[-1])
ldau = True
ldau_luj = {}
if line.find('LDAUL') != -1:
L = line.split('=')[-1].split()
if line.find('LDAUU') != -1:
U = line.split('=')[-1].split()
if line.find('LDAUJ') != -1:
J = line.split('=')[-1].split()
# create dictionary
if ldau:
for i, symbol in enumerate(atomtypes):
ldau_luj[symbol] = {
'L': int(L[i]),
'U': float(U[i]),
'J': float(J[i])
}
self.dict_params['ldau_luj'] = ldau_luj
self.ldau = ldau
self.ldauprint = ldauprint
self.ldautype = ldautype
self.ldau_luj = ldau_luj
return ldau, ldauprint, ldautype, ldau_luj
def get_xc_functional(self):
"""Returns the XC functional or the pseudopotential type
If a XC recipe is set explicitly with 'xc', this is returned.
Otherwise, the XC functional associated with the
pseudopotentials (LDA, PW91 or PBE) is returned.
The string is always cast to uppercase for consistency
in checks."""
if self.input_params.get('xc', None):
return self.input_params['xc'].upper()
if self.input_params.get('pp', None):
return self.input_params['pp'].upper()
raise ValueError('No xc or pp found.')
# Methods for reading information from OUTCAR files:
def read_energy(self, all=None, lines=None):
"""Method to read energy from OUTCAR file.
Depreciated: use get_potential_energy() instead"""
if not lines:
lines = self.load_file('OUTCAR')
[energy_free, energy_zero] = [0, 0]
if all:
energy_free = []
energy_zero = []
for line in lines:
# Free energy
if line.lower().startswith(' free energy toten'):
if all:
energy_free.append(float(line.split()[-2]))
else:
energy_free = float(line.split()[-2])
# Extrapolated zero point energy
if line.startswith(' energy without entropy'):
if all:
energy_zero.append(float(line.split()[-1]))
else:
energy_zero = float(line.split()[-1])
return [energy_free, energy_zero]
def read_forces(self, all=False, lines=None):
"""Method that reads forces from OUTCAR file.
If 'all' is switched on, the forces for all ionic steps
in the OUTCAR file be returned, in other case only the
forces for the last ionic configuration is returned."""
if not lines:
lines = self.load_file('OUTCAR')
if all:
all_forces = []
for n, line in enumerate(lines):
if 'TOTAL-FORCE' in line:
forces = []
for i in range(len(self.atoms)):
forces.append(
np.array(
[float(f) for f in lines[n + 2 + i].split()[3:6]]))
if all:
all_forces.append(np.array(forces)[self.resort])
if all:
return np.array(all_forces)
return np.array(forces)[self.resort]
def read_fermi(self, lines=None):
"""Method that reads Fermi energy from OUTCAR file"""
if not lines:
lines = self.load_file('OUTCAR')
E_f = None
for line in lines:
if 'E-fermi' in line:
E_f = float(line.split()[2])
return E_f
def read_dipole(self, lines=None):
"""Read dipole from OUTCAR"""
if not lines:
lines = self.load_file('OUTCAR')
dipolemoment = np.zeros([1, 3])
for line in lines:
if 'dipolmoment' in line:
dipolemoment = np.array([float(f) for f in line.split()[1:4]])
return dipolemoment
def read_mag(self, lines=None):
if not lines:
lines = self.load_file('OUTCAR')
p = self.int_params
q = self.list_float_params
if self.spinpol:
magnetic_moment = self._read_magnetic_moment(lines=lines)
if ((p['lorbit'] is not None and p['lorbit'] >= 10)
or (p['lorbit'] is None and q['rwigs'])):
magnetic_moments = self._read_magnetic_moments(lines=lines)
else:
warn('Magnetic moment data not written in OUTCAR (LORBIT<10),'
' setting magnetic_moments to zero.\nSet LORBIT>=10'
' to get information on magnetic moments')
magnetic_moments = np.zeros(len(self.atoms))
else:
magnetic_moment = 0.0
magnetic_moments = np.zeros(len(self.atoms))
return magnetic_moment, magnetic_moments
def _read_magnetic_moments(self, lines=None):
"""Read magnetic moments from OUTCAR.
Only reads the last occurrence. """
if not lines:
lines = self.load_file('OUTCAR')
magnetic_moments = np.zeros(len(self.atoms))
magstr = 'magnetization (x)'
# Search for the last occurrence
nidx = -1
for n, line in enumerate(lines):
if magstr in line:
nidx = n
# Read that occurrence
if nidx > -1:
for m in range(len(self.atoms)):
magnetic_moments[m] = float(lines[nidx + m + 4].split()[-1])
return magnetic_moments[self.resort]
def _read_magnetic_moment(self, lines=None):
"""Read magnetic moment from OUTCAR"""
if not lines:
lines = self.load_file('OUTCAR')
for line in lines:
if 'number of electron ' in line:
_ = line.split()[-1]
magnetic_moment = 0.0 if _ == "magnetization" else float(_)
return magnetic_moment
def read_nbands(self, lines=None):
"""Read number of bands from OUTCAR"""
if not lines:
lines = self.load_file('OUTCAR')
for line in lines:
line = self.strip_warnings(line)
if 'NBANDS' in line:
return int(line.split()[-1])
return None
def read_convergence(self, lines=None):
"""Method that checks whether a calculation has converged."""
if not lines:
lines = self.load_file('OUTCAR')
converged = None
# First check electronic convergence
for line in lines:
# VASP 6 actually labels loop exit reason
if 'aborting loop' in line:
converged = 'because EDIFF is reached' in line
# NOTE: 'EDIFF was not reached (unconverged)'
# and
# 'because hard stop was set'
# will result in unconverged
break
# determine convergence by attempting to reproduce VASP's
# internal logic
if 'EDIFF ' in line:
ediff = float(line.split()[2])
if 'total energy-change' in line:
# I saw this in an atomic oxygen calculation. it
# breaks this code, so I am checking for it here.
if 'MIXING' in line:
continue
split = line.split(':')
a = float(split[1].split('(')[0])
b = split[1].split('(')[1][0:-2]
# sometimes this line looks like (second number wrong format!):
# energy-change (2. order) :-0.2141803E-08 ( 0.2737684-111)
# we are checking still the first number so
# let's "fix" the format for the second one
if 'e' not in b.lower():
# replace last occurrence of - (assumed exponent) with -e
bsplit = b.split('-')
bsplit[-1] = 'e' + bsplit[-1]
b = '-'.join(bsplit).replace('-e', 'e-')
b = float(b)
if [abs(a), abs(b)] < [ediff, ediff]:
converged = True
else:
converged = False
continue
# Then if ibrion in [1,2,3] check whether ionic relaxation
# condition been fulfilled
if (self.int_params['ibrion'] in [1, 2, 3]
and self.int_params['nsw'] not in [0]):
if not self.read_relaxed():
converged = False
else:
converged = True
return converged
def read_k_point_weights(self, filename):
"""Read k-point weighting. Normally named IBZKPT."""
lines = self.load_file(filename)
if 'Tetrahedra\n' in lines:
N = lines.index('Tetrahedra\n')
else:
N = len(lines)
kpt_weights = []
for n in range(3, N):
kpt_weights.append(float(lines[n].split()[3]))
kpt_weights = np.array(kpt_weights)
kpt_weights /= np.sum(kpt_weights)
return kpt_weights
def read_relaxed(self, lines=None):
"""Check if ionic relaxation completed"""
if not lines:
lines = self.load_file('OUTCAR')
for line in lines:
if 'reached required accuracy' in line:
return True
return False
def read_spinpol(self, lines=None):
"""Method which reads if a calculation from spinpolarized using OUTCAR.
Depreciated: Use get_spin_polarized() instead.
"""
if not lines:
lines = self.load_file('OUTCAR')
for line in lines:
if 'ISPIN' in line:
if int(line.split()[2]) == 2:
self.spinpol = True
else:
self.spinpol = False
return self.spinpol
def strip_warnings(self, line):
"""Returns empty string instead of line from warnings in OUTCAR."""
if line[0] == "|":
return ""
return line
@property
def txt(self):
return self._txt
@txt.setter
def txt(self, txt):
if isinstance(txt, PurePath):
txt = str(txt)
self._txt = txt
def get_number_of_grid_points(self):
raise NotImplementedError
def get_pseudo_density(self):
raise NotImplementedError
def get_pseudo_wavefunction(self, n=0, k=0, s=0, pad=True):
raise NotImplementedError
def get_bz_k_points(self):
raise NotImplementedError
[docs]
def read_vib_freq(self, lines=None) -> Tuple[List[float], List[float]]:
"""Read vibrational frequencies.
Returns:
List of real and list of imaginary frequencies
(imaginary number as real number).
"""
freq = []
i_freq = []
if not lines:
lines = self.load_file('OUTCAR')
for line in lines:
data = line.split()
if 'THz' in data:
if 'f/i=' not in data:
freq.append(float(data[-2]))
else:
i_freq.append(float(data[-2]))
return freq, i_freq
def _read_massweighted_hessian_xml(self) -> np.ndarray:
"""Read the Mass Weighted Hessian from vasprun.xml.
Returns:
The Mass Weighted Hessian as np.ndarray from the xml file.
Raises a ReadError if the reader is not able to read the Hessian.
Converts to ASE units for VASP version 6.
"""
file = self._indir('vasprun.xml')
try:
tree = ElementTree.iterparse(file)
hessian = None
for event, elem in tree:
if elem.tag == 'dynmat':
for i, entry in enumerate(
elem.findall('varray[@name="hessian"]/v')):
text_split = entry.text.split()
if not text_split:
raise ElementTree.ParseError(
"Could not find varray hessian!")
if i == 0:
n_items = len(text_split)
hessian = np.zeros((n_items, n_items))
assert isinstance(hessian, np.ndarray)
hessian[i, :] = np.array(
[float(val) for val in text_split])
if i != n_items - 1:
raise ElementTree.ParseError(
"Hessian is not quadratic!")
# VASP6+ uses THz**2 as unit, not mEV**2 as before
for entry in elem.findall('i[@name="unit"]'):
if entry.text.strip() == 'THz^2':
conv = ase.units._amu / ase.units._e / \
1e-4 * (2 * np.pi)**2 # THz**2 to eV**2
# VASP6 uses factor 2pi
# 1e-4 = (angstrom to meter times Hz to THz) squared
# = (1e10 times 1e-12)**2
break
else: # Catch changes in VASP
vasp_version_error_msg = (
f'The file "{file}" is from a '
'non-supported VASP version. '
'Not sure what unit the Hessian '
'is in, aborting.')
raise calculator.ReadError(vasp_version_error_msg)
else:
conv = 1.0 # VASP version <6 unit is meV**2
assert isinstance(hessian, np.ndarray)
hessian *= conv
if hessian is None:
raise ElementTree.ParseError("Hessian is None!")
except ElementTree.ParseError as exc:
incomplete_msg = (
f'The file "{file}" is incomplete, '
'and no DFT data was available. '
'This is likely due to an incomplete calculation.')
raise calculator.ReadError(incomplete_msg) from exc
# VASP uses the negative definition of the hessian compared to ASE
return -hessian
[docs]
def get_vibrations(self) -> VibrationsData:
"""Get a VibrationsData Object from a VASP Calculation.
Returns:
VibrationsData object.
Note that the atoms in the VibrationsData object can be resorted.
Uses the (mass weighted) Hessian from vasprun.xml, different masses
in the POTCAR can therefore result in different results.
Note the limitations concerning k-points and symmetry mentioned in
the VASP-Wiki.
"""
mass_weighted_hessian = self._read_massweighted_hessian_xml()
# get indices of freely moving atoms, i.e. respect constraints.
indices = VibrationsData.indices_from_constraints(self.atoms)
# save the corresponding sorted atom numbers
sort_indices = np.array(self.sort)[indices]
# mass weights = 1/sqrt(mass)
mass_weights = np.repeat(self.atoms.get_masses()[sort_indices]**-0.5, 3)
# get the unweighted hessian = H_w / m_w / m_w^T
# ugly and twice the work, but needed since vasprun.xml does
# not have the unweighted ase.vibrations.vibration will do the
# opposite in Vibrations.read
hessian = mass_weighted_hessian / \
mass_weights / mass_weights[:, np.newaxis]
return VibrationsData.from_2d(self.atoms[self.sort], hessian, indices)
def get_nonselfconsistent_energies(self, bee_type):
""" Method that reads and returns BEE energy contributions
written in OUTCAR file.
"""
assert bee_type == 'beefvdw'
cmd = 'grep -32 "BEEF xc energy contributions" OUTCAR | tail -32'
p = os.popen(cmd, 'r')
s = p.readlines()
p.close()
xc = np.array([])
for line in s:
l_ = float(line.split(":")[-1])
xc = np.append(xc, l_)
assert len(xc) == 32
return xc
#####################################
# Below defines helper functions
# for the VASP calculator
#####################################
def check_atoms(atoms: ase.Atoms) -> None:
"""Perform checks on the atoms object, to verify that
it can be run by VASP.
A CalculatorSetupError error is raised if the atoms are not supported.
"""
# Loop through all check functions
for check in (check_atoms_type, check_cell, check_pbc):
check(atoms)
def check_cell(atoms: ase.Atoms) -> None:
"""Check if there is a zero unit cell.
Raises CalculatorSetupError if the cell is wrong.
"""
if atoms.cell.rank < 3:
raise calculator.CalculatorSetupError(
"The lattice vectors are zero! "
"This is the default value - please specify a "
"unit cell.")
def check_pbc(atoms: ase.Atoms) -> None:
"""Check if any boundaries are not PBC, as VASP
cannot handle non-PBC.
Raises CalculatorSetupError.
"""
if not atoms.pbc.all():
raise calculator.CalculatorSetupError(
"Vasp cannot handle non-periodic boundaries. "
"Please enable all PBC, e.g. atoms.pbc=True")
def check_atoms_type(atoms: ase.Atoms) -> None:
"""Check that the passed atoms object is in fact an Atoms object.
Raises CalculatorSetupError.
"""
if not isinstance(atoms, ase.Atoms):
raise calculator.CalculatorSetupError(
'Expected an Atoms object, '
'instead got object of type {}'.format(type(atoms)))