def test_shape():
def in_circle(pos):
return pos[0]**2 + pos[1]**2 < 3
lat = lattice.honeycomb(norbs=1)
sites = list(lat.shape(in_circle, (0, 0))())
sites_alt = list()
sl0, sl1 = lat.sublattices
for x in range(-2, 3):
for y in range(-2, 3):
tag = (x, y)
for site in (sl0(*tag), sl1(*tag)):
if in_circle(site.pos):
sites_alt.append(site)
assert len(sites) == len(sites_alt)
assert set(sites) == set(sites_alt)
raises(ValueError, lat.shape(in_circle, (10, 10))().__next__)
# Check if narrow ribbons work.
for period in (0, 1), (1, 0), (1, -1):
vec = lat.vec(period)
sym = lattice.TranslationalSymmetry(vec)
def shape(pos):
return abs(pos[0] * vec[1] - pos[1] * vec[0]) < 10
sites = list(lat.shape(shape, (0, 0))(sym))
assert len(sites) > 35
def test_shape():
def in_circle(pos):
return pos[0] ** 2 + pos[1] ** 2 < 3
lat = lattice.honeycomb()
sites = list(lat.shape(in_circle, (0, 0))())
sites_alt = list()
sl0, sl1 = lat.sublattices
for x in xrange(-2, 3):
for y in xrange(-2, 3):
tag = (x, y)
for site in (sl0(*tag), sl1(*tag)):
if in_circle(site.pos):
sites_alt.append(site)
assert len(sites) == len(sites_alt)
assert_equal(set(sites), set(sites_alt))
assert_raises(ValueError, lat.shape(in_circle, (10, 10))().next)
# Check if narrow ribbons work.
for period in (0, 1), (1, 0), (1, -1):
vec = lat.vec(period)
sym = lattice.TranslationalSymmetry(vec)
def shape(pos):
return abs(pos[0] * vec[1] - pos[1] * vec[0]) < 10
sites = list(lat.shape(shape, (0, 0))(sym))
assert len(sites) > 35
def test_neighbors():
lat = lattice.honeycomb(1e-10, norbs=1)
num_nth_nearest = [len(lat.neighbors(n)) for n in range(5)]
assert num_nth_nearest == [2, 3, 6, 3, 6]
lat = lattice.general([(0, 1e8, 0, 0), (0, 0, 1e8, 0)], norbs=1)
num_nth_nearest = [len(lat.neighbors(n)) for n in range(5)]
assert num_nth_nearest == [1, 2, 2, 2, 4]
lat = lattice.chain(1e-10, norbs=1)
num_nth_nearest = [len(lat.neighbors(n)) for n in range(5)]
assert num_nth_nearest == 5 * [1]
def test_neighbors():
lat = lattice.honeycomb(1e-10)
num_nth_nearest = [len(lat.neighbors(n)) for n in range(5)]
assert num_nth_nearest == [2, 3, 6, 3, 6]
lat = lattice.square(1e8)
num_nth_nearest = [len(lat.neighbors(n)) for n in range(5)]
assert num_nth_nearest == [1, 2, 2, 2, 4]
lat = lattice.chain(1e-10)
num_nth_nearest = [len(lat.neighbors(n)) for n in range(5)]
assert num_nth_nearest == 5 * [1]
def test_error_minus_9(r=10):
"""Test if MUMPSError -9 is properly caught by increasing memory"""
graphene = honeycomb(norbs=1)
a, b = graphene.sublattices
def circle(pos):
x, y = pos
return x**2 + y**2 < r**2
syst = Builder()
syst[graphene.shape(circle, (0, 0))] = -0.0001
for kind in [((0, 0), b, a), ((0, 1), b, a), ((-1, 1), b, a)]:
syst[HoppingKind(*kind)] = -1
ham = syst.finalized().hamiltonian_submatrix(sparse=True)
# No need to check result, it's enough if no exception is raised
MUMPSContext().factor(ham)
def test_error_minus_9(r=10):
"""Test if MUMPSError -9 is properly caught by increasing memory"""
graphene = honeycomb()
a, b = graphene.sublattices
def circle(pos):
x, y = pos
return x**2 + y**2 < r**2
sys = Builder()
sys[graphene.shape(circle, (0,0))] = -0.0001
for kind in [((0, 0), b, a), ((0, 1), b, a), ((-1, 1), b, a)]:
sys[HoppingKind(*kind)] = - 1
ham = sys.finalized().hamiltonian_submatrix(sparse=True)
# No need to check result, it's enough if no exception is raised
MUMPSContext().factor(ham)
