Stuff for testing things¶
- class ase.calculators.test.FreeElectrons(restart=None, ignore_bad_restart_file=<object object>, label=None, atoms=None, directory='.', **kwargs)[source]¶
Free-electron band calculator.
Parameters:
- nvalence: int
Number of electrons
- kpts: dict
K-point specification.
Example: >>> from ase.calculators.test import FreeElectrons >>> calc = FreeElectrons(nvalence=1, kpts={‘path’: ‘GXL’})
Basic calculator implementation.
- restart: str
Prefix for restart file. May contain a directory. Default is None: don’t restart.
- ignore_bad_restart_file: bool
Deprecated, please do not use. Passing more than one positional argument to Calculator() is deprecated and will stop working in the future. Ignore broken or missing restart file. By default, it is an error if the restart file is missing or broken.
- directory: str or PurePath
Working directory in which to read and write files and perform calculations.
- label: str
Name used for all files. Not supported by all calculators. May contain a directory, but please use the directory parameter for that instead.
- atoms: Atoms object
Optional Atoms object to which the calculator will be attached. When restarting, atoms will get its positions and unit-cell updated from file.
- calculate(atoms, properties, system_changes)[source]¶
Do the calculation.
- properties: list of str
List of what needs to be calculated. Can be any combination of ‘energy’, ‘forces’, ‘stress’, ‘dipole’, ‘charges’, ‘magmom’ and ‘magmoms’.
- system_changes: list of str
List of what has changed since last calculation. Can be any combination of these six: ‘positions’, ‘numbers’, ‘cell’, ‘pbc’, ‘initial_charges’ and ‘initial_magmoms’.
Subclasses need to implement this, but can ignore properties and system_changes if they want. Calculated properties should be inserted into results dictionary like shown in this dummy example:
self.results = {'energy': 0.0, 'forces': np.zeros((len(atoms), 3)), 'stress': np.zeros(6), 'dipole': np.zeros(3), 'charges': np.zeros(len(atoms)), 'magmom': 0.0, 'magmoms': np.zeros(len(atoms))}
The subclass implementation should first call this implementation to set the atoms attribute and create any missing directories.