def test_correct_arguments():
pytest.raises(ValueError, lambda: R2.e_x(R2.e_x))
pytest.raises(ValueError, lambda: R2.e_x(R2.dx))
pytest.raises(ValueError, lambda: Commutator(R2.e_x, R2.x))
pytest.raises(ValueError, lambda: Commutator(R2.dx, R2.e_x))
pytest.raises(ValueError, lambda: Differential(Differential(R2.e_x)))
pytest.raises(ValueError, lambda: R2.dx(R2.x))
pytest.raises(ValueError, lambda: TensorProduct(R2.e_x, R2.dx))
pytest.raises(ValueError, lambda: LieDerivative(R2.dx, R2.dx))
pytest.raises(ValueError, lambda: LieDerivative(R2.x, R2.dx))
pytest.raises(ValueError, lambda: CovarDerivativeOp(R2.dx, []))
pytest.raises(ValueError, lambda: CovarDerivativeOp(R2.x, []))
a = Symbol('a')
pytest.raises(ValueError, lambda: intcurve_series(R2.dx, a, R2_r.point([1, 2])))
pytest.raises(ValueError, lambda: intcurve_series(R2.x, a, R2_r.point([1, 2])))
pytest.raises(ValueError, lambda: intcurve_diffequ(R2.dx, a, R2_r.point([1, 2])))
pytest.raises(ValueError, lambda: intcurve_diffequ(R2.x, a, R2_r.point([1, 2])))
pytest.raises(ValueError, lambda: contravariant_order(R2.e_x + R2.dx))
pytest.raises(ValueError, lambda: contravariant_order(R2.dx**2))
pytest.raises(ValueError, lambda: covariant_order(R2.e_x + R2.dx))
pytest.raises(ValueError, lambda: contravariant_order(R2.e_x*R2.e_y))
pytest.raises(ValueError, lambda: covariant_order(R2.dx*R2.dy))
assert covariant_order(Integer(0), True) == -1
assert contravariant_order(Integer(0), True) == -1
def test_correct_arguments():
pytest.raises(ValueError, lambda: R2.e_x(R2.e_x))
pytest.raises(ValueError, lambda: R2.e_x(R2.dx))
pytest.raises(ValueError, lambda: Commutator(R2.e_x, R2.x))
pytest.raises(ValueError, lambda: Commutator(R2.dx, R2.e_x))
pytest.raises(ValueError, lambda: Differential(Differential(R2.e_x)))
pytest.raises(ValueError, lambda: R2.dx(R2.x))
pytest.raises(ValueError, lambda: TensorProduct(R2.e_x, R2.dx))
pytest.raises(ValueError, lambda: LieDerivative(R2.dx, R2.dx))
pytest.raises(ValueError, lambda: LieDerivative(R2.x, R2.dx))
pytest.raises(ValueError, lambda: CovarDerivativeOp(R2.dx, []))
pytest.raises(ValueError, lambda: CovarDerivativeOp(R2.x, []))
a = Symbol('a')
pytest.raises(ValueError, lambda: intcurve_series(R2.dx, a, R2_r.point([1, 2])))
pytest.raises(ValueError, lambda: intcurve_series(R2.x, a, R2_r.point([1, 2])))
pytest.raises(ValueError, lambda: intcurve_diffequ(R2.dx, a, R2_r.point([1, 2])))
pytest.raises(ValueError, lambda: intcurve_diffequ(R2.x, a, R2_r.point([1, 2])))
pytest.raises(ValueError, lambda: contravariant_order(R2.e_x + R2.dx))
pytest.raises(ValueError, lambda: contravariant_order(R2.dx**2))
pytest.raises(ValueError, lambda: covariant_order(R2.e_x + R2.dx))
pytest.raises(ValueError, lambda: contravariant_order(R2.e_x*R2.e_y))
pytest.raises(ValueError, lambda: covariant_order(R2.dx*R2.dy))
assert covariant_order(Integer(0), True) == -1
assert contravariant_order(Integer(0), True) == -1
def test_lie_derivative():
assert LieDerivative(R2.e_x, R2.y) == R2.e_x(R2.y) == 0
assert LieDerivative(R2.e_x, R2.x) == R2.e_x(R2.x) == 1
assert LieDerivative(R2.e_x, R2.e_x) == Commutator(R2.e_x, R2.e_x) == 0
assert LieDerivative(R2.e_x, R2.e_r) == Commutator(R2.e_x, R2.e_r)
assert LieDerivative(R2.e_x + R2.e_y, R2.x) == 1
assert LieDerivative(R2.e_x, TensorProduct(R2.dx, R2.dy))(R2.e_x,
R2.e_y) == 0
def test_lie_derivative():
assert LieDerivative(R2.e_x, R2.y) == R2.e_x(R2.y) == 0
assert LieDerivative(R2.e_x, R2.x) == R2.e_x(R2.x) == 1
assert LieDerivative(R2.e_x, R2.e_x) == Commutator(R2.e_x, R2.e_x) == 0
assert LieDerivative(R2.e_x, R2.e_r) == Commutator(R2.e_x, R2.e_r)
assert LieDerivative(R2.e_x + R2.e_y, R2.x) == 1
assert LieDerivative(
R2.e_x, TensorProduct(R2.dx, R2.dy))(R2.e_x, R2.e_y) == 0
def test_functional_diffgeom_ch3():
x0, y0 = symbols('x0, y0', extended_real=True)
x, y, t = symbols('x, y, t', extended_real=True)
f = Function('f')
b1 = Function('b1')
b2 = Function('b2')
p_r = R2_r.point([x0, y0])
s_field = f(R2.x, R2.y)
v_field = b1(R2.x) * R2.e_x + b2(R2.y) * R2.e_y
assert v_field.rcall(s_field).rcall(p_r).doit() == b1(x0) * Derivative(
f(x0, y0), x0) + b2(y0) * Derivative(f(x0, y0), y0)
assert R2.e_x(R2.r**2).rcall(p_r) == 2 * x0
v = R2.e_x + 2 * R2.e_y
s = R2.r**2 + 3 * R2.x
assert v.rcall(s).rcall(p_r).doit() == 2 * x0 + 4 * y0 + 3
circ = -R2.y * R2.e_x + R2.x * R2.e_y
series = intcurve_series(circ, t, R2_r.point([1, 0]), coeffs=True)
series_x, series_y = zip(*series)
assert all(term == cos(t).taylor_term(i, t)
for i, term in enumerate(series_x))
assert all(term == sin(t).taylor_term(i, t)
for i, term in enumerate(series_y))
def test_functional_diffgeom_ch3():
x0, y0 = symbols('x0, y0', extended_real=True)
x, y, t = symbols('x, y, t', extended_real=True)
f = Function('f')
b1 = Function('b1')
b2 = Function('b2')
p_r = R2_r.point([x0, y0])
s_field = f(R2.x, R2.y)
v_field = b1(R2.x)*R2.e_x + b2(R2.y)*R2.e_y
assert v_field.rcall(s_field).rcall(p_r).doit() == b1(
x0)*Derivative(f(x0, y0), x0) + b2(y0)*Derivative(f(x0, y0), y0)
assert R2.e_x(R2.r**2).rcall(p_r) == 2*x0
v = R2.e_x + 2*R2.e_y
s = R2.r**2 + 3*R2.x
assert v.rcall(s).rcall(p_r).doit() == 2*x0 + 4*y0 + 3
circ = -R2.y*R2.e_x + R2.x*R2.e_y
series = intcurve_series(circ, t, R2_r.point([1, 0]), coeffs=True)
series_x, series_y = zip(*series)
assert all(term == cos(t).taylor_term(i, t)
for i, term in enumerate(series_x))
assert all(term == sin(t).taylor_term(i, t)
for i, term in enumerate(series_y))