def _find_mirror(self, axis):
"""
Looks for mirror symmetry of specified type about axis. Possible
types are "h" or "vd". Horizontal (h) mirrors are perpendicular to
the axis while vertical (v) or diagonal (d) mirrors are parallel. v
mirrors has atoms lying on the mirror plane while d mirrors do
not.
"""
mirror_type = ""
# First test whether the axis itself is the normal to a mirror plane.
if self.is_valid_op(SymmOp.reflection(axis)):
self.symmops.append(SymmOp.reflection(axis))
mirror_type = "h"
else:
# Iterate through all pairs of atoms to find mirror
for s1, s2 in itertools.combinations(self.centered_mol, 2):
if s1.species_and_occu == s2.species_and_occu:
normal = s1.coords - s2.coords
if np.dot(normal, axis) < self.tol:
op = SymmOp.reflection(normal)
if self.is_valid_op(op):
self.symmops.append(op)
if len(self.rot_sym) > 1:
mirror_type = "d"
for v, r in self.rot_sym:
if not np.linalg.norm(v - axis) < self.tol:
if np.dot(v, normal) < self.tol:
mirror_type = "v"
break
else:
mirror_type = "v"
break
return mirror_type
def _find_mirror(self, axis):
"""
Looks for mirror symmetry of specified type about axis. Possible
types are "h" or "vd". Horizontal (h) mirrors are perpendicular to
the axis while vertical (v) or diagonal (d) mirrors are parallel. v
mirrors has atoms lying on the mirror plane while d mirrors do
not.
"""
mirror_type = ""
# First test whether the axis itself is the normal to a mirror plane.
if self.is_valid_op(SymmOp.reflection(axis)):
self.symmops.append(SymmOp.reflection(axis))
mirror_type = "h"
else:
# Iterate through all pairs of atoms to find mirror
for s1, s2 in itertools.combinations(self.centered_mol, 2):
if s1.species_and_occu == s2.species_and_occu:
normal = s1.coords - s2.coords
if np.dot(normal, axis) < self.tol:
op = SymmOp.reflection(normal)
if self.is_valid_op(op):
self.symmops.append(op)
if len(self.rot_sym) > 1:
mirror_type = "d"
for v, r in self.rot_sym:
if not np.linalg.norm(v - axis) < self.tol:
if np.dot(v, normal) < self.tol:
mirror_type = "v"
break
else:
mirror_type = "v"
break
return mirror_type
def test_reflection(self):
normal = np.random.rand(3)
origin = np.random.rand(3)
refl = SymmOp.reflection(normal, origin)
point = np.random.rand(3)
newcoord = refl.operate(point)
# Distance to the plane should be negatives of each other.
self.assertAlmostEqual(np.dot(newcoord - origin, normal), -np.dot(point - origin, normal))
def test_reflection(self):
normal = np.random.rand(3)
origin = np.random.rand(3)
refl = SymmOp.reflection(normal, origin)
point = np.random.rand(3)
newcoord = refl.operate(point)
# Distance to the plane should be negatives of each other.
self.assertAlmostEqual(np.dot(newcoord - origin, normal),
-np.dot(point - origin, normal))
