def test_tensor_prod_scalar(Nphi, Nr, basis, ncc_first, dealias, dtype):
c, d, b, phi, r, x, y = basis(Nphi, Nr, dealias=dealias, dtype=dtype)
f = field.Field(dist=d, bases=(b.radial_basis, ), dtype=dtype)
g = field.Field(dist=d, bases=(b, ), dtype=dtype)
f['g'] = r**4
g['g'] = 3 * x**2 + 2 * y
T = operators.Gradient(operators.Gradient(f, c), c).evaluate()
vars = [g]
if ncc_first:
U0 = T * g
else:
U0 = g * T
U1 = U0.reinitialize(ncc=True, ncc_vars=vars)
problem = problems.LBVP(vars)
problem.add_equation((f * g, 0))
solver = solvers.LinearBoundaryValueSolver(
problem,
matsolver='SuperluNaturalSpsolve',
matrix_coupling=[False, True])
U1.store_ncc_matrices(vars, solver.subproblems)
U0 = U0.evaluate()
U0.change_scales(1)
U1 = U1.evaluate_as_ncc()
assert np.allclose(U0['g'], U1['g'])
def test_tensor_dot_vector(Nphi, Nr, basis, ncc_first, dealias, dtype):
c, d, b, phi, r, x, y = basis(Nphi, Nr, dealias=dealias, dtype=dtype)
f = field.Field(dist=d, bases=(b.radial_basis, ), dtype=dtype)
g = field.Field(dist=d, bases=(b, ), dtype=dtype)
f['g'] = r**4
g['g'] = 3 * x**2 + 2 * y
T = operators.Gradient(operators.Gradient(f, c), c).evaluate()
u = operators.Gradient(g, c).evaluate()
vars = [u]
if ncc_first:
w0 = dot(T, u)
else:
w0 = dot(u, T)
w1 = w0.reinitialize(ncc=True, ncc_vars=vars)
problem = problems.LBVP(vars)
problem.add_equation((f * u, 0))
solver = solvers.LinearBoundaryValueSolver(
problem,
matsolver='SuperluNaturalSpsolve',
matrix_coupling=[False, True])
w1.store_ncc_matrices(vars, solver.subproblems)
w0 = w0.evaluate()
w0.change_scales(1)
w1 = w1.evaluate_as_ncc()
assert np.allclose(w0['g'], w1['g'])
def test_multiply_tensor_tensor(Nphi, Ntheta, Nr, dealias, basis):
c, d, b, phi, theta, r, x, y, z = basis(Nphi, Ntheta, Nr, dealias,
np.complex128)
f = field.Field(dist=d, bases=(b, ), dtype=np.complex128)
f['g'] = x**3 + 2 * y**3 + 3 * z**3
u = operators.Gradient(f, c).evaluate()
T = operators.Gradient(u, c).evaluate()
Q = (T * T).evaluate()
Qg = T['g'][:, :, None, None, ...] * T['g'][None, None, ...]
assert np.allclose(Q['g'], Qg)
def test_implicit_transpose_tensor(Nphi, Ntheta, Nr, k, dealias, dtype, basis):
c, d, b, phi, theta, r, x, y, z = basis(Nphi, Ntheta, Nr, k, dealias,
dtype)
ct, st, cp, sp = np.cos(theta), np.sin(theta), np.cos(phi), np.sin(phi)
u = field.Field(dist=d, bases=(b, ), tensorsig=(c, ), dtype=dtype)
u.preset_scales(b.domain.dealias)
u['g'][2] = r**2 * st * (2 * ct**2 * cp - r * ct**3 * sp +
r**3 * cp**3 * st**5 * sp**3 + r * ct * st**2 *
(cp**3 + sp**3))
u['g'][1] = r**2 * (2 * ct**3 * cp - r * cp**3 * st**4 +
r**3 * ct * cp**3 * st**5 * sp**3 -
1 / 16 * r * np.sin(2 * theta)**2 *
(-7 * sp + np.sin(3 * phi)))
u['g'][0] = r**2 * sp * (-2 * ct**2 + r * ct * cp * st**2 * sp -
r**3 * cp**2 * st**5 * sp**3)
T = operators.Gradient(u, c).evaluate()
Ttg = np.transpose(np.copy(T['g']), (1, 0, 2, 3, 4))
Tt = field.Field(dist=d, bases=(b, ), tensorsig=(
c,
c,
), dtype=dtype)
trans = lambda A: operators.TransposeComponents(A)
problem = problems.LBVP([Tt])
problem.add_equation((trans(Tt), T))
# Solver
solver = solvers.LinearBoundaryValueSolver(problem)
solver.solve()
assert np.allclose(Tt['g'], Ttg)
def test_interpolate_radius_tensor(Nphi, Nr, k, dealias, basis, dtype,
r_interp):
c, d, b, phi, r, x, y = basis(Nphi, Nr, k, dealias, dtype)
f = field.Field(dist=d, bases=(b, ), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = x**4 + 2 * y**4
u = operators.Gradient(f, c)
T = operators.Gradient(u, c)
v = T(r=r_interp).evaluate()
r = np.array([[r_interp]])
x, y = c.cartesian(phi, r)
ex = np.array([-np.sin(phi), np.cos(phi)])
ey = np.array([np.cos(phi), np.sin(phi)])
exex = ex[:, None, ...] * ex[None, ...]
eyey = ey[:, None, ...] * ey[None, ...]
vg = 12 * x**2 * exex + 24 * y**2 * eyey
assert np.allclose(v['g'], vg)
def calculate2():
op_dot = neg * operators.DotProduct(u, operators.Gradient(u, c))
u_rhs.preset_layout(u_rhs.dist.grid_layout)
u_rhs['g'] = op_dot.evaluate()['g']
# R = ez cross u
op = negOm * operators.CrossProduct(ez, u)
u_rhs['g'] += op.evaluate()['g']
def test_divergence_radial_vector(Nr, dealias, basis, dtype):
c, d, b, phi, theta, r, x, y, z = basis(1, 1, Nr, 1, dtype=dtype)
f = field.Field(dist=d, bases=(b,), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = r**4/3
u = operators.Gradient(f, c)
h = operators.Divergence(u).evaluate()
hg = 20/3*r**2
assert np.allclose(h['g'], hg)
def test_multiply_vector_vector(Nphi, Ntheta, Nr, dealias, basis):
c, d, b, phi, theta, r, x, y, z = basis(Nphi, Ntheta, Nr, dealias,
np.complex128)
f = field.Field(dist=d, bases=(b, ), dtype=np.complex128)
f['g'] = x**3 + 2 * y**3 + 3 * z**3
u = operators.Gradient(f, c).evaluate()
T = (u * u).evaluate()
Tg = u['g'][None, ...] * u['g'][:, None, ...]
assert np.allclose(T['g'], Tg)
def test_gradient_radial_scalar(Nr, dealias, basis, dtype):
Nphi = 1
c, d, b, phi, r, x, y = basis(Nphi, Nr, dealias, dtype)
f = field.Field(dist=d, bases=(b, ), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = r**4
u = operators.Gradient(f, c).evaluate()
ug = [0 * r * phi, 4 * r**3 + 0 * phi]
assert np.allclose(u['g'], ug)
def test_divergence_vector(Nphi, Ntheta, Nr, dealias, basis, dtype):
c, d, b, phi, theta, r, x, y, z = basis(Nphi, Ntheta, Nr, dealias, dtype)
f = field.Field(dist=d, bases=(b,), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = x**3 + 2*y**3 + 3*z**3
u = operators.Gradient(f, c)
h = operators.Divergence(u).evaluate()
hg = 6*x + 12*y + 18*z
assert np.allclose(h['g'], hg)
def test_ball_diffusion(Lmax, Nmax, Leig, radius, bc, dtype):
# Bases
c = coords.SphericalCoordinates('phi', 'theta', 'r')
d = distributor.Distributor((c, ))
b = basis.BallBasis(c, (2 * (Lmax + 1), Lmax + 1, Nmax + 1),
radius=radius,
dtype=dtype)
b_S2 = b.S2_basis()
phi, theta, r = b.local_grids((1, 1, 1))
# Fields
A = field.Field(dist=d, bases=(b, ), tensorsig=(c, ), dtype=dtype)
φ = field.Field(dist=d, bases=(b, ), dtype=dtype)
τ_A = field.Field(dist=d, bases=(b_S2, ), tensorsig=(c, ), dtype=dtype)
λ = field.Field(name='λ', dist=d, dtype=dtype)
# Parameters and operators
div = lambda A: operators.Divergence(A)
grad = lambda A: operators.Gradient(A, c)
curl = lambda A: operators.Curl(A)
lap = lambda A: operators.Laplacian(A, c)
trans = lambda A: operators.TransposeComponents(A)
radial = lambda A, index: operators.RadialComponent(A, index=index)
angular = lambda A, index: operators.AngularComponent(A, index=index)
Lift = lambda A: operators.Lift(A, b, -1)
# Problem
problem = problems.EVP([φ, A, τ_A], λ)
problem.add_equation((div(A), 0))
problem.add_equation((-λ * A + grad(φ) - lap(A) + Lift(τ_A), 0))
if bc == 'no-slip':
problem.add_equation((A(r=radius), 0))
elif bc == 'stress-free':
E = 1 / 2 * (grad(A) + trans(grad(A)))
problem.add_equation((radial(A(r=radius), 0), 0))
problem.add_equation((radial(angular(E(r=radius), 0), 1), 0))
elif bc == 'potential':
ell_func = lambda ell: ell + 1
ell_1 = lambda A: operators.SphericalEllProduct(A, c, ell_func)
problem.add_equation(
(radial(grad(A)(r=radius), 0) + ell_1(A)(r=radius) / radius, 0))
elif bc == 'conducting':
problem.add_equation((φ(r=radius), 0))
problem.add_equation((angular(A(r=radius), 0), 0))
elif bc == 'pseudo':
problem.add_equation((radial(A(r=radius), 0), 0))
problem.add_equation((angular(curl(A)(r=radius), 0), 0))
# Solver
solver = solvers.EigenvalueSolver(problem)
if not solver.subproblems[Leig].group[1] == Leig:
raise ValueError("subproblems indexed in a strange way")
solver.solve_dense(solver.subproblems[Leig])
i_sort = np.argsort(solver.eigenvalues)
solver.eigenvalues = solver.eigenvalues[i_sort]
λ_analytic = analytic_eigenvalues(Leig, Nmax + 1, bc, r0=radius)
if (bc == 'stress-free' and Leig == 1):
# add null space solution
λ_analytic = np.append(0, λ_analytic)
assert np.allclose(solver.eigenvalues[:Nmax // 4], λ_analytic[:Nmax // 4])
def test_divergence_vector(Nphi, Nr, dealias, basis, dtype):
c, d, b, phi, r, x, y = basis(Nphi, Nr, dealias, dtype)
f = field.Field(dist=d, bases=(b, ), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = 3 * x**4 + 2 * y * x
grad = lambda A: operators.Gradient(A, c)
div = lambda A: operators.Divergence(A)
S = div(grad(f)).evaluate()
Sg = 36 * x**2
assert np.allclose(S['g'], Sg)
def test_gradient_radial_scalar(Nr, dealias, basis, dtype):
Nphi = Ntheta = 1
c, d, b, phi, theta, r, x, y, z = basis(Nphi, Ntheta, Nr, dealias, dtype)
f = field.Field(dist=d, bases=(b,), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = fg = r**4/3
u = operators.Gradient(f, c).evaluate()
ug = 0 * u['g']
ug[2] = 4/3*r**3
assert np.allclose(u['g'], ug)
def test_gradient_scalar(Nphi, Nr, dealias, basis, dtype):
c, d, b, phi, r, x, y = basis(Nphi, Nr, dealias, dtype)
f = field.Field(dist=d, bases=(b, ), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = 3 * x**2 + 2 * y
u = operators.Gradient(f, c).evaluate()
ex = np.array([-np.sin(phi) + 0. * r, np.cos(phi) + 0. * r])
ey = np.array([np.cos(phi) + 0. * r, np.sin(phi) + 0. * r])
ug = 6 * x * ex + 2 * ey
assert np.allclose(u['g'], ug)
def test_divergence_radial_vector(Nr, dealias, basis, dtype):
Nphi = 1
c, d, b, phi, r, x, y = basis(Nphi, Nr, dealias, dtype=dtype)
f = field.Field(dist=d, bases=(b, ), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = r**2
grad = lambda A: operators.Gradient(A, c)
div = lambda A: operators.Divergence(A)
h = div(grad(f)).evaluate()
hg = 4
assert np.allclose(h['g'], hg)
def test_gradient_scalar(Nphi, Ntheta, Nr, dealias, basis, dtype):
c, d, b, phi, theta, r, x, y, z = basis(Nphi, Ntheta, Nr, dealias, dtype)
f = field.Field(dist=d, bases=(b,), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = fg = 3*x**2 + 2*y*z
u = operators.Gradient(f, c).evaluate()
ug = 0 * u['g']
ug[2] = (6*x**2+4*y*z)/r
ug[1] = -2*(y**3+x**2*(y-3*z)-y*z**2)/(r**2*np.sin(theta))
ug[0] = 2*x*(-3*y+z)/(r*np.sin(theta))
assert np.allclose(u['g'], ug)
def test_divergence_tensor(Nphi, Nr, dealias, basis, dtype):
c, d, b, phi, r, x, y = basis(Nphi, Nr, dealias, dtype)
v = field.Field(dist=d, tensorsig=(c, ), bases=(b, ), dtype=dtype)
v.preset_scales(b.domain.dealias)
ex = np.array([-np.sin(phi) + 0. * r, np.cos(phi) + 0. * r])
ey = np.array([np.cos(phi) + 0. * r, np.sin(phi) + 0. * r])
v['g'] = 4 * x**3 * ey + 3 * y**2 * ey
grad = lambda A: operators.Gradient(A, c)
div = lambda A: operators.Divergence(A)
U = div(grad(v)).evaluate()
Ug = (24 * x + 6) * ey
assert np.allclose(U['g'], Ug)
def test_explicit_trace_tensor(Nphi, Nr, k, dealias, basis, dtype, layout):
c, d, b, phi, r, x, y = basis(Nphi, Nr, k, dealias, dtype)
u = field.Field(dist=d, bases=(b, ), tensorsig=(c, ), dtype=dtype)
u.preset_scales(b.domain.dealias)
ex = np.array([-np.sin(phi) + 0. * r, np.cos(phi) + 0. * r])
ey = np.array([np.cos(phi) + 0. * r, np.sin(phi) + 0. * r])
u['g'] = 4 * x**3 * ey + 3 * y**2 * ey
T = operators.Gradient(u, c).evaluate()
fg = T['g'][0, 0] + T['g'][1, 1]
T.change_layout(layout)
f = operators.Trace(T).evaluate()
assert np.allclose(f['g'], fg)
def test_multiply_scalar_vector(Nphi, Ntheta, Nr, dealias, basis):
c, d, b, phi, theta, r, x, y, z = basis(Nphi, Ntheta, Nr, dealias,
np.complex128)
phi, theta, r = b.local_grids(b.domain.dealias)
x, y, z = c.cartesian(phi, theta, r)
f = field.Field(dist=d, bases=(b, ), dtype=np.complex128)
f.preset_scales(b.domain.dealias)
f['g'] = x**3 + 2 * y**3 + 3 * z**3
u = operators.Gradient(f, c).evaluate()
v = (f * u).evaluate()
vg = f['g'][None, ...] * u['g']
assert np.allclose(v['g'], vg)
def test_gradient_radial_vector(Nr, dealias, basis, dtype):
Nphi = Ntheta = 1
c, d, b, phi, theta, r, x, y, z = basis(Nphi, Ntheta, Nr, dealias, dtype=dtype)
f = field.Field(dist=d, bases=(b,), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = r**4 / 3
grad = lambda A: operators.Gradient(A, c)
T = grad(grad(f)).evaluate()
Tg = 0 * T['g']
Tg[0,0] = 4 / 3 * r**2
Tg[1,1] = 4 / 3 * r**2
Tg[2,2] = 4 * r**2
assert np.allclose(T['g'], Tg)
def calculate1():
Du.preset_layout(Du.dist.coeff_layout)
Du['c'] = 0
op = operators.Gradient(u, c)
op.out = Du
op.evaluate()
op_dot = neg * operators.DotProduct(u, Du)
u_rhs.preset_layout(u_rhs.dist.grid_layout)
u_rhs['g'] = op_dot.evaluate()['g']
# R = ez cross u
op = negOm * operators.CrossProduct(ez, u)
u_rhs['g'] += op.evaluate()['g']
def test_interpolate_radius_vector(Nphi, Nr, k, dealias, basis, dtype,
r_interp):
c, d, b, phi, r, x, y = basis(Nphi, Nr, k, dealias, dtype)
f = field.Field(dist=d, bases=(b, ), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = x**4 + 2 * y**4
u = operators.Gradient(f, c)
v = u(r=r_interp).evaluate()
r = np.array([[r_interp]])
x, y = c.cartesian(phi, r)
ex = np.array([-np.sin(phi), np.cos(phi)])
ey = np.array([np.cos(phi), np.sin(phi)])
vg = 4 * x**3 * ex + 8 * y**3 * ey
assert np.allclose(v['g'], vg)
def test_gradient_radial_vector(Nr, dealias, basis, dtype):
Nphi = 1
c, d, b, phi, r, x, y = basis(Nphi, Nr, dealias, dtype)
f = field.Field(dist=d, bases=(b, ), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = r**4
grad = lambda A: operators.Gradient(A, c)
T = grad(grad(f)).evaluate()
er = np.array([[[0]], [[1]]])
ephi = np.array([[[1]], [[0]]])
erer = er[:, None, ...] * er[None, ...]
ephiephi = ephi[:, None, ...] * ephi[None, ...]
Tg = 12 * r**2 * erer + 4 * r**2 * ephiephi
assert np.allclose(T['g'], Tg)
def test_dot_product_vector_vector(Nphi, Ntheta, Nr, dealias, basis):
c, d, b, phi, theta, r, x, y, z = basis(Nphi, Ntheta, Nr, dealias,
np.complex128)
f = field.Field(dist=d, bases=(b, ), dtype=np.complex128)
f['g'] = z
ez = operators.Gradient(f, c).evaluate()
u = field.Field(dist=d, bases=(b, ), tensorsig=(c, ), dtype=np.complex128)
u['g'][2] = (6 * x**2 + 4 * y * z) / r
u['g'][1] = -2 * (y**3 + x**2 *
(y - 3 * z) - y * z**2) / (r**2 * np.sin(theta))
u['g'][0] = 2 * x * (-3 * y + z) / (r * np.sin(theta))
h = arithmetic.DotProduct(ez, u).evaluate()
hg = np.sum(ez['g'] * u['g'], axis=0)
assert np.allclose(h['g'], hg)
def test_tensor_dot_tensor(Nphi, Nr, basis, ncc_first, dealias, dtype):
c, d, b, phi, r, x, y = basis(Nphi, Nr, dealias=dealias, dtype=dtype)
f = field.Field(dist=d, bases=(b.radial_basis, ), dtype=dtype)
f['g'] = r**6
U = operators.Gradient(operators.Gradient(f, c), c).evaluate()
T = field.Field(dist=d, bases=(b, ), tensorsig=(
c,
c,
), dtype=dtype)
z = 0
theta = np.pi / 2.
T['g'][1, 1] = (6 * x**2 + 4 * y * z) / r**2
T['g'][1, 0] = T['g'][0, 1] = 2 * x * (z - 3 * y) / (r**2 * np.sin(theta))
T['g'][0, 0] = 6 * y**2 / (x**2 + y**2)
vars = [T]
if ncc_first:
W0 = dot(T, U)
else:
W0 = dot(U, T)
W1 = W0.reinitialize(ncc=True, ncc_vars=vars)
problem = problems.LBVP(vars)
problem.add_equation((f * T, 0))
solver = solvers.LinearBoundaryValueSolver(
problem,
matsolver='SuperluNaturalSpsolve',
matrix_coupling=[False, True])
W1.store_ncc_matrices(vars, solver.subproblems)
W0 = W0.evaluate()
W0.change_scales(1)
W1 = W1.evaluate_as_ncc()
assert np.allclose(W0['g'], W1['g'])
def test_gradient_vector(Nphi, Ntheta, Nr, dealias, basis, dtype):
c, d, b, phi, theta, r, x, y, z = basis(Nphi, Ntheta, Nr, dealias, dtype)
f = field.Field(dist=d, bases=(b,), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = 3*x**2 + 2*y*z
grad = lambda A: operators.Gradient(A, c)
T = grad(grad(f)).evaluate()
Tg = 0 * T['g']
Tg[2,2] = (6*x**2+4*y*z)/r**2
Tg[2,1] = Tg[1,2] = -2*(y**3+x**2*(y-3*z)-y*z**2)/(r**3*np.sin(theta))
Tg[2,0] = Tg[0,2] = 2*x*(z-3*y)/(r**2*np.sin(theta))
Tg[1,1] = 6*x**2/(r**2*np.sin(theta)**2) - (6*x**2+4*y*z)/r**2
Tg[1,0] = Tg[0,1] = -2*x*(x**2+y**2+3*y*z)/(r**3*np.sin(theta)**2)
Tg[0,0] = 6*y**2/(x**2+y**2)
assert np.allclose(T['g'], Tg)
def test_gradient_vector(Nphi, Nr, dealias, basis, dtype):
c, d, b, phi, r, x, y = basis(Nphi, Nr, dealias, dtype)
f = field.Field(dist=d, bases=(b, ), dtype=dtype)
f.preset_scales(b.domain.dealias)
f['g'] = 3 * x**4 + 2 * y * x
grad = lambda A: operators.Gradient(A, c)
T = grad(grad(f)).evaluate()
ex = np.array([-np.sin(phi) + 0. * r, np.cos(phi) + 0. * r])
ey = np.array([np.cos(phi) + 0. * r, np.sin(phi) + 0. * r])
exex = ex[:, None, ...] * ex[None, ...]
eyex = ey[:, None, ...] * ex[None, ...]
exey = ex[:, None, ...] * ey[None, ...]
eyey = ey[:, None, ...] * ey[None, ...]
Tg = 36 * x**2 * exex + 2 * (exey + eyex)
assert np.allclose(T['g'], Tg)
def test_cross_product(Nphi, Ntheta, Nr, dealias, basis):
c, d, b, phi, theta, r, x, y, z = basis(Nphi, Ntheta, Nr, dealias,
np.complex128)
f = field.Field(dist=d, bases=(b, ), dtype=np.complex128)
f['g'] = z
ez = operators.Gradient(f, c).evaluate()
u = field.Field(dist=d, bases=(b, ), tensorsig=(c, ), dtype=np.complex128)
u['g'][2] = (6 * x**2 + 4 * y * z) / r
u['g'][1] = -2 * (y**3 + x**2 *
(y - 3 * z) - y * z**2) / (r**2 * np.sin(theta))
u['g'][0] = 2 * x * (-3 * y + z) / (r * np.sin(theta))
h = arithmetic.CrossProduct(ez, u).evaluate()
hg = np.zeros(h['g'].shape, dtype=h['g'].dtype)
hg[0] = -ez['g'][1] * u['g'][2] + ez['g'][2] * u['g'][1]
hg[1] = -ez['g'][2] * u['g'][0] + ez['g'][0] * u['g'][2]
hg[2] = -ez['g'][0] * u['g'][1] + ez['g'][1] * u['g'][0]
assert np.allclose(h['g'], hg)
def test_disk_AdvectiveCFL(Nr, Nphi, timestepper, dtype, dealias):
radius = 2
# Bases
c, d, db, phi, r, x, y = build_disk(Nphi,
Nr,
radius,
dealias,
dtype=dtype,
grid_scale=1)
# Fields
f = field.Field(name='f', dist=d, bases=(db, ), dtype=dtype)
f['g'] = x * y
u = operators.Gradient(f, c).evaluate()
# AdvectiveCFL initialization
cfl = operators.AdvectiveCFL(u, c)
cfl_freq = cfl.evaluate()['g']
comparison_freq = np.abs(u['g'][0]) / cfl.cfl_spacing()[0]
comparison_freq += np.abs(u['g'][1]) / cfl.cfl_spacing()[1]
assert np.allclose(cfl_freq, comparison_freq)
def test_spherical_shell_AdvectiveCFL(Lmax, Nmax, timestepper, dtype, dealias):
radii = (0.5, 2)
# Bases
c, d, b, phi, theta, r, x, y, z = build_shell(2 * (Lmax + 1), (Lmax + 1),
(Nmax + 1),
radii,
dealias,
dtype=dtype,
grid_scale=1)
# Fields
f = field.Field(name='f', dist=d, bases=(b, ), dtype=dtype)
f['g'] = x * y * z
u = operators.Gradient(f, c).evaluate()
# AdvectiveCFL initialization
cfl = operators.AdvectiveCFL(u, c)
cfl_freq = cfl.evaluate()['g']
comparison_freq = np.sqrt(u['g'][0]**2 +
u['g'][1]**2) / cfl.cfl_spacing()[0]
comparison_freq += np.abs(u['g'][2]) / cfl.cfl_spacing()[1]
assert np.allclose(cfl_freq, comparison_freq)