Stress¶

class py4vasp.data.Stress(raw_data)¶

Bases: py4vasp.data._trajectory.DataTrajectory

The stress acting on the unit cell for selected steps of the simulation.

You can use this class to analyze the stress on the shape of the cell. In particular, you can check whether the stress is small at the end of the calculation.

Parameters

raw_stress (RawStress) – Dataclass containing the raw stress tensor and associated structure data.

Examples

If you access a method of this class, the result will depend on the steps that you selected with the [] operator. Without any selection the results from the final step will be used.

>>> calc.stress.read()

To select the results for all steps, you don’t specify the array boundaries.

>>> calc.stress[:].read()

You can also select specific steps or a subset of steps as follows

>>> calc.stress[5].read()
>>> calc.stress[1:6].read()

Methods Summary

from_dict(dict_)	Initialize refinement class from data dictionary
from_file([file])	Read the data dictionary from the given file.
print()	Print a string representation of this class to standard output.
read()	Read the stress and associated structural information for one or more selected steps of the trajectory.
to_dict()	Read the stress and associated structural information for one or more selected steps of the trajectory.

Methods Documentation

classmethod from_dict(dict_)¶

Initialize refinement class from data dictionary

Parameters

data_dict (dict) – Data dictionary that contains one or more different raw data sources.

classmethod from_file(file=None)¶

Read the data dictionary from the given file.

You want to use this method if you want to avoid using the Calculation wrapper, for example because you renamed the output of the VASP calculation.

Parameters

file (str or Path or raw.File) – Filename from which the data is extracted. If not present the default filename is used. Alternatively, you can open the file yourself and pass the File object. In that case, you need to take care the file is properly closed again and be aware the generated instance of this class becomes unusable after the file is closed.

Returns

The returned instance handles opening and closing the file for every function called on it, unless a File object in which case this is left to the user.

Return type

DataBase

print()¶

Print a string representation of this class to standard output.

read()¶

Read the stress and associated structural information for one or more selected steps of the trajectory.

Returns

Contains the stress for all selected steps and the structural information to know on which cell the stress acts.

Return type

dict

Examples

If you access this method, the result will depend on the steps of the class that you selected with the [] operator. Without any selection the results from the final step will be used.

>>> calc.stress.read()

To select the results for all steps, you don’t specify the array boundaries.

>>> calc.stress[:].read()

You can also select specific steps or a subset of steps as follows

>>> calc.stress[5].read()
>>> calc.stress[1:6].read()

to_dict()¶

Read the stress and associated structural information for one or more selected steps of the trajectory.

Returns

Contains the stress for all selected steps and the structural information to know on which cell the stress acts.

Return type

dict

Examples

If you access this method, the result will depend on the steps of the class that you selected with the [] operator. Without any selection the results from the final step will be used.

>>> calc.stress.read()

To select the results for all steps, you don’t specify the array boundaries.

>>> calc.stress[:].read()

You can also select specific steps or a subset of steps as follows

>>> calc.stress[5].read()
>>> calc.stress[1:6].read()