diff --git a/kwant/continuum/discretizer.py b/kwant/continuum/discretizer.py
index c6b95297b0f890167c2f907cd6e2af9dcac50017..ad79642aea7b737aa4c26fe5c534dabf5f421380 100644
--- a/kwant/continuum/discretizer.py
+++ b/kwant/continuum/discretizer.py
@@ -601,12 +601,12 @@ def _builder_value(expr, coords, grid_spacing, onsite,
{str(k.func) for k in map_func_calls})
# check if all argument names are valid python identifiers
- for name in arg_names:
- if not (name.isidentifier() and not iskeyword(name)):
+ for arg_name in arg_names:
+ if not (arg_name.isidentifier() and not iskeyword(arg_name)):
raise ValueError("Invalid name in used symbols: {}\n"
"Names of symbols used in Hamiltonian "
"must be valid Python identifiers and "
- "may not be keywords".format(name))
+ "may not be keywords".format(arg_name))
arg_names = ', '.join(sorted(arg_names))
diff --git a/kwant/continuum/tests/test_discretizer.py b/kwant/continuum/tests/test_discretizer.py
index 47efbe3ad7e05ab5fe7b17e0e39b7300301ded9e..149150d54c63e1cf71892eec650e1ffd84b313a2 100644
--- a/kwant/continuum/tests/test_discretizer.py
+++ b/kwant/continuum/tests/test_discretizer.py
@@ -45,7 +45,7 @@ x, y, z = sympy.symbols('x y z', commutative=False)
ax, ay, az = sympy.symbols('a_x a_y a_z')
a = sympy.symbols('a')
-wf = _wf
+wf = _wf
Psi = wf(x, y, z)
A, B = sympy.symbols('A B', commutative=False)
@@ -62,7 +62,7 @@ def test_reading_coordinates(commutative):
kx**2 + ky**2 + kz**2 : ['x', 'y', 'z'],
ky**2 + kz**2 : ['y', 'z'],
kz**2 : ['z'],
- kx * A(x,y) * kx : ['x'],
+ kx * A(x, y) * kx : ['x'],
kx**2 + kz * B(y) : ['x', 'z'],
}
for inp, out in test.items():
@@ -78,7 +78,7 @@ def test_reading_coordinates_matrix():
(sympy.Matrix([kx**2 + ky**2 + kz**2]) , ['x', 'y', 'z']),
(sympy.Matrix([ky**2 + kz**2]) , ['y', 'z']),
(sympy.Matrix([kz**2]) , ['z']),
- (sympy.Matrix([kx * A(x,y) * kx]) , ['x']),
+ (sympy.Matrix([kx * A(x, y) * kx]) , ['x']),
(sympy.Matrix([kx**2 + kz * B(y)]) , ['x', 'z']),
]
for inp, out in test:
@@ -113,7 +113,7 @@ def test_simple_derivations(commutative):
kz**2 : {(0,): 2/a**2, (1,): -1/a**2},
}
non_commutative_test = {
- kx * A(x,y) * kx : {(1, ): -A(a/2 + x, y)/a**2,
+ kx * A(x, y) * kx : {(1, ): -A(a/2 + x, y)/a**2,
(0, ): A(-a/2 + x, y)/a**2 + A(a/2 + x, y)/a**2},
kx**2 + kz * B(y) : {(1, 0): -1/a**2, (0, 1): -I*B(y)/(2*a),
(0, 0): 2/a**2},
@@ -160,7 +160,7 @@ def test_simple_derivations_matrix():
ky**2 + kz**2 : {(0, 1): -1/a**2, (0, 0): 4/a**2,
(1, 0): -1/a**2},
kz**2 : {(0,): 2/a**2, (1,): -1/a**2},
- kx * A(x,y) * kx : {(1, ): -A(a/2 + x, y)/a**2,
+ kx * A(x, y) * kx : {(1, ): -A(a/2 + x, y)/a**2,
(0, ): A(-a/2 + x, y)/a**2 + A(a/2 + x, y)/a**2},
kx**2 + kz * B(y) : {(1, 0): -1/a**2, (0, 1): -I*B(y)/(2*a),
(0, 0): 2/a**2},
@@ -195,9 +195,9 @@ def test_simple_derivations_matrix():
def test_integer_float_input():
test = {
- 0: {(0,0,0): 0},
- 1: {(0,0,0): 1},
- 5: {(0,0,0): 5},
+ 0: {(0, 0, 0): 0},
+ 1: {(0, 0, 0): 1},
+ 5: {(0, 0, 0): 5},
}
for inp, out in test.items():
@@ -266,7 +266,7 @@ def test_different_discrete_coordinates():
'z', {
(0,): ky**2 + kx**2 + 2/a**2, (1,): -1/a**2
}
- ) ,
+ ),
]
for inp, out in test:
got, _ = discretize_symbolic(kx**2 + ky**2 + kz**2, inp)
@@ -298,8 +298,8 @@ def test_matrix_with_zeros():
Matrix = sympy.Matrix
symbolic, _ = discretize_symbolic("[[k_x*A(x)*k_x, 0], [0, k_x*A(x)*k_x]]")
output = {
- (0,) : Matrix([[A(-a/2 + x)/a**2 + A(a/2 + x)/a**2, 0], [0, A(-a/2 + x)/a**2 + A(a/2 + x)/a**2]]),
- (1,) : Matrix([[-A(a/2 + x)/a**2, 0], [0, -A(a/2 + x)/a**2]]),
+ (0,): Matrix([[A(-a/2 + x)/a**2 + A(a/2 + x)/a**2, 0], [0, A(-a/2 + x)/a**2 + A(a/2 + x)/a**2]]),
+ (1,): Matrix([[-A(a/2 + x)/a**2, 0], [0, -A(a/2 + x)/a**2]]),
}
assert symbolic == output
@@ -326,7 +326,7 @@ def test_numeric_functions_basic_symbolic():
assert +1j * p['t'] == builder[lat(1), lat(0)](None, None, **p)
-@pytest.mark.parametrize('commutative', [ True, False])
+@pytest.mark.parametrize('commutative', [True, False])
def test_numeric_function_coords_from_site(commutative):
tb = {(0,): sympy.symbols('x', commutative=commutative)}
builder = build_discretized(tb, 'x')
@@ -336,7 +336,6 @@ def test_numeric_function_coords_from_site(commutative):
assert (onsite(lat(0)) == 0 and onsite(lat(1)) == 1)
-
def test_numeric_functions_not_discrete_coords():
builder = discretize('k_y + y', 'x')
lat = next(iter(builder.sites()))[0]
@@ -401,8 +400,12 @@ def test_numeric_functions_with_subs(e_to_subs, e, subs):
hop_direct = builder_direct[lat(0), lat(1)](None, None, **p)
hop_subs = builder_subs[lat(0), lat(1)](None, None, **p)
- assert hop_direct == hop_subs
+ assert hop_direct == hop_subs
+
+def test_onsite_hopping_function_name():
+ template = str(discretize('A * k_x'))
+ assert 'def hopping' in template
def test_numeric_functions_advance():