feat: epsilon tensors moved to dirac submodule, tests added

This commit is contained in:
Fabian Joswig 2021-12-23 12:00:10 +01:00
parent b50346dcf3
commit c8cb0e4cb8
3 changed files with 36 additions and 12 deletions

View file

@ -22,6 +22,30 @@ identity = np.array(
dtype=complex)
def epsilon_tensor(i, j, k):
"""Rank-3 epsilon tensor
Based on https://codegolf.stackexchange.com/a/160375
"""
test_set = set((i, j, k))
if not (test_set <= set((1, 2, 3)) or test_set <= set((0, 1, 2))):
raise Exception("Unexpected input", i, j, k)
return (i - j) * (j - k) * (k - i) / 2
def epsilon_tensor_rank4(i, j, k, o):
"""Rank-4 epsilon tensor
Extension of https://codegolf.stackexchange.com/a/160375
"""
test_set = set((i, j, k, o))
if not (test_set <= set((1, 2, 3, 4)) or test_set <= set((0, 1, 2, 3))):
raise Exception("Unexpected input", i, j, k, o)
return (i - j) * (j - k) * (k - i) * (i - o) * (j - o) * (o - k) / 12
def Grid_gamma(gamma_tag):
"""Returns gamma matrix in Grid labeling."""
if gamma_tag == 'Identity':

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@ -298,18 +298,6 @@ def read_Fourquark_hd5(path, filestem, ens_id, idl=None, vertices=["VA", "AV"]):
return result_dict
def _epsilon_tensor(i, j, k, o):
"""Rank-4 epsilon tensor
Extension of https://codegolf.stackexchange.com/a/160375
"""
test_set = set((i, j, k, o))
if not (test_set <= set((1, 2, 3, 4)) or test_set <= set((0, 1, 2, 3))):
raise Exception("Unexpected input", i, j, k, o)
return (i - j) * (j - k) * (k - i) * (i - o) * (j - o) * (o - k) / 12
def _get_lorentz_names(name):
assert len(name) == 2

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@ -32,3 +32,15 @@ def test_grid_dirac():
pe.dirac.Grid_gamma(gamma)
with pytest.raises(Exception):
pe.dirac.Grid_gamma('Not a gamma matrix')
def test_epsilon_tensor():
check = {(1, 2, 3) : 1.0,
(3, 1, 2) : 1.0,
(2, 3, 1) : 1.0,
(1, 1, 1) : 0.0,
(3, 2, 1) : -1.0,
(1, 3, 2) : -1.0,
(1, 1, 3) : 0.0}
for key, value in check.items():
assert pe.dirac.epsilon_tensor(*key) == value