def get_triplets_integration_weights(interaction,
frequency_points,
sigma,
is_collision_matrix=False,
neighboring_phonons=False,
lang='C'):
triplets = interaction.get_triplets_at_q()[0]
frequencies = interaction.get_phonons()[0]
num_band = frequencies.shape[1]
g_zero = None
if is_collision_matrix:
g = np.empty(
(3, len(triplets), len(frequency_points), num_band, num_band),
dtype='double',
order='C')
else:
g = np.empty(
(2, len(triplets), len(frequency_points), num_band, num_band),
dtype='double',
order='C')
g[:] = 0
if sigma:
if lang == 'C':
import phono3py._phono3py as phono3c
phono3c.triplets_integration_weights_with_sigma(
g, frequency_points, triplets, frequencies, sigma)
else:
for i, tp in enumerate(triplets):
f1s = frequencies[tp[1]]
f2s = frequencies[tp[2]]
for j, k in list(np.ndindex((num_band, num_band))):
f1 = f1s[j]
f2 = f2s[k]
g0 = gaussian(frequency_points - f1 - f2, sigma)
g[0, i, :, j, k] = g0
g1 = gaussian(frequency_points + f1 - f2, sigma)
g2 = gaussian(frequency_points - f1 + f2, sigma)
g[1, i, :, j, k] = g1 - g2
if len(g) == 3:
g[2, i, :, j, k] = g0 + g1 + g2
else:
if lang == 'C':
g_zero = np.zeros(g.shape[1:], dtype='byte', order='C')
_set_triplets_integration_weights_c(
g,
g_zero,
interaction,
frequency_points,
neighboring_phonons=neighboring_phonons)
else:
_set_triplets_integration_weights_py(g, interaction,
frequency_points)
return g, g_zero
def get_triplets_integration_weights(
interaction,
frequency_points,
sigma,
sigma_cutoff=None,
is_collision_matrix=False,
lang="C",
):
"""Calculate triplets integration weights.
Returns
-------
g : ndarray
Triplets integration weights.
shape=(2 or 3, triplets, freq_points, bands, bands), dtype='double'.
g_zero : ndarray
Location of strictly zero elements.
shape=(triplets, freq_points, bands, bands), dtype='byte'
"""
triplets = interaction.get_triplets_at_q()[0]
frequencies = interaction.get_phonons()[0]
num_band = frequencies.shape[1]
g_zero = None
if is_collision_matrix:
g = np.empty(
(3, len(triplets), len(frequency_points), num_band, num_band),
dtype="double",
order="C",
)
else:
g = np.empty(
(2, len(triplets), len(frequency_points), num_band, num_band),
dtype="double",
order="C",
)
g[:] = 0
if sigma:
if lang == "C":
import phono3py._phono3py as phono3c
g_zero = np.zeros(g.shape[1:], dtype="byte", order="C")
if sigma_cutoff is None:
cutoff = -1
else:
cutoff = float(sigma_cutoff)
# cutoff < 0 disables g_zero feature.
phono3c.triplets_integration_weights_with_sigma(
g, g_zero, frequency_points, triplets, frequencies, sigma, cutoff
)
else:
for i, tp in enumerate(triplets):
f1s = frequencies[tp[1]]
f2s = frequencies[tp[2]]
for j, k in list(np.ndindex((num_band, num_band))):
f1 = f1s[j]
f2 = f2s[k]
g0 = gaussian(frequency_points - f1 - f2, sigma)
g[0, i, :, j, k] = g0
g1 = gaussian(frequency_points + f1 - f2, sigma)
g2 = gaussian(frequency_points - f1 + f2, sigma)
g[1, i, :, j, k] = g1 - g2
if len(g) == 3:
g[2, i, :, j, k] = g0 + g1 + g2
else:
if lang == "C":
g_zero = np.zeros(g.shape[1:], dtype="byte", order="C")
_set_triplets_integration_weights_c(
g,
g_zero,
interaction,
frequency_points,
)
else:
_set_triplets_integration_weights_py(g, interaction, frequency_points)
return g, g_zero