phonopy/test/spectrum/test_velocity.py

29 lines
770 B
Python

"""Tests for velocity calculation from MD data."""
import os
import numpy as np
from phonopy.interface.vasp import read_XDATCAR
from phonopy.spectrum.velocity import Velocity
data_dir = os.path.dirname(os.path.abspath(__file__))
def test_Velocity():
"""Test Velocity class."""
lattice, positions = read_XDATCAR(os.path.join(data_dir, "XDATCAR"))
v = Velocity(positions=positions, lattice=lattice, timestep=2)
v.run()
velocity = v.get_velocities()
velocity_cmp = np.loadtxt(os.path.join(data_dir, "velocities.dat"))
assert (np.abs(velocity.ravel() - velocity_cmp.ravel()) < 1e-1).all()
def _show(velocity):
print(velocity)
def _write(velocity):
np.savetxt(os.path.join(data_dir, "velocities.dat"), velocity.reshape((-1, 3)))