Beispiel #1
0
def test_curl(typecode):
    K0 = FunctionSpace(N[0], 'F', dtype=typecode.upper())
    K1 = FunctionSpace(N[1], 'F', dtype=typecode.upper())
    K2 = FunctionSpace(N[2], 'F', dtype=typecode)
    T = TensorProductSpace(comm, (K0, K1, K2), dtype=typecode)
    X = T.local_mesh(True)
    K = T.local_wavenumbers()
    Tk = VectorSpace(T)
    u = shenfun.TrialFunction(Tk)
    v = shenfun.TestFunction(Tk)

    U = Array(Tk)
    U_hat = Function(Tk)
    curl_hat = Function(Tk)
    curl_ = Array(Tk)

    # Initialize a Taylor Green vortex
    U[0] = np.sin(X[0]) * np.cos(X[1]) * np.cos(X[2])
    U[1] = -np.cos(X[0]) * np.sin(X[1]) * np.cos(X[2])
    U[2] = 0
    U_hat = Tk.forward(U, U_hat)
    Uc = U_hat.copy()
    U = Tk.backward(U_hat, U)
    U_hat = Tk.forward(U, U_hat)
    assert allclose(U_hat, Uc)

    divu_hat = project(div(U_hat), T)
    divu = Array(T)
    divu = T.backward(divu_hat, divu)
    assert allclose(divu, 0)

    curl_hat[0] = 1j * (K[1] * U_hat[2] - K[2] * U_hat[1])
    curl_hat[1] = 1j * (K[2] * U_hat[0] - K[0] * U_hat[2])
    curl_hat[2] = 1j * (K[0] * U_hat[1] - K[1] * U_hat[0])

    curl_ = Tk.backward(curl_hat, curl_)

    w_hat = Function(Tk)
    w_hat = inner(v, curl(U_hat), output_array=w_hat)
    A = inner(v, u)
    for i in range(3):
        w_hat[i] = A[i].solve(w_hat[i])

    w = Array(Tk)
    w = Tk.backward(w_hat, w)
    assert allclose(w, curl_)

    u_hat = Function(Tk)
    u_hat = inner(v, U, output_array=u_hat)
    for i in range(3):
        u_hat[i] = A[i].solve(u_hat[i])

    uu = Array(Tk)
    uu = Tk.backward(u_hat, uu)

    assert allclose(u_hat, U_hat)
Beispiel #2
0
def test_curl2():
    # Test projection of curl

    K0 = FunctionSpace(N[0], 'C', bc=(0, 0))
    K1 = FunctionSpace(N[1], 'F', dtype='D')
    K2 = FunctionSpace(N[2], 'F', dtype='d')
    K3 = FunctionSpace(N[0], 'C')

    T = TensorProductSpace(comm, (K0, K1, K2))
    TT = TensorProductSpace(comm, (K3, K1, K2))
    X = T.local_mesh(True)
    K = T.local_wavenumbers(False)
    Tk = VectorSpace(T)
    TTk = VectorSpace([T, T, TT])

    U = Array(Tk)
    U_hat = Function(Tk)
    curl_hat = Function(TTk)
    curl_ = Array(TTk)

    # Initialize a Taylor Green vortex
    U[0] = np.sin(X[0]) * np.cos(X[1]) * np.cos(X[2]) * (1 - X[0]**2)
    U[1] = -np.cos(X[0]) * np.sin(X[1]) * np.cos(X[2]) * (1 - X[0]**2)
    U[2] = 0
    U_hat = Tk.forward(U, U_hat)
    Uc = U_hat.copy()
    U = Tk.backward(U_hat, U)
    U_hat = Tk.forward(U, U_hat)
    assert allclose(U_hat, Uc)

    # Compute curl first by computing each term individually
    curl_hat[0] = 1j * (K[1] * U_hat[2] - K[2] * U_hat[1])
    curl_[0] = T.backward(
        curl_hat[0], curl_[0])  # No x-derivatives, still in Dirichlet space
    dwdx_hat = project(Dx(U_hat[2], 0, 1), TT)  # Need to use space without bc
    dvdx_hat = project(Dx(U_hat[1], 0, 1), TT)  # Need to use space without bc
    dwdx = Array(TT)
    dvdx = Array(TT)
    dwdx = TT.backward(dwdx_hat, dwdx)
    dvdx = TT.backward(dvdx_hat, dvdx)
    curl_hat[1] = 1j * K[2] * U_hat[0]
    curl_hat[2] = -1j * K[1] * U_hat[0]
    curl_[1] = T.backward(curl_hat[1], curl_[1])
    curl_[2] = T.backward(curl_hat[2], curl_[2])
    curl_[1] -= dwdx
    curl_[2] += dvdx

    # Now do it with project
    w_hat = project(curl(U_hat), TTk)
    w = Array(TTk)
    w = TTk.backward(w_hat, w)
    assert allclose(w, curl_)
def test_transform(typecode, dim):
    s = (True,)
    if comm.Get_size() > 2 and dim > 2:
        s = (True, False)

    for slab in s:
        for shape in product(*([sizes]*dim)):
            bases = []
            for n in shape[:-1]:
                bases.append(FunctionSpace(n, 'F', dtype=typecode.upper()))
            bases.append(FunctionSpace(shape[-1], 'F', dtype=typecode))

            fft = TensorProductSpace(comm, bases, dtype=typecode, slab=slab)

            if comm.rank == 0:
                grid = [c.size for c in fft.subcomm]
                print('grid:{} shape:{} typecode:{}'
                      .format(grid, shape, typecode))

            U = random_like(fft.forward.input_array)

            F = fft.forward(U)
            V = fft.backward(F)
            assert allclose(V, U)

            # Alternative method
            fft.forward.input_array[...] = U
            fft.forward(fast_transform=False)
            fft.backward(fast_transform=False)
            V = fft.backward.output_array
            assert allclose(V, U)

            TT = VectorSpace(fft)
            U = Array(TT)
            V = Array(TT)
            F = Function(TT)
            U[:] = random_like(U)
            F = TT.forward(U, F)
            V = TT.backward(F, V)
            assert allclose(V, U)

            TM = CompositeSpace([fft, fft])
            U = Array(TM)
            V = Array(TM)
            F = Function(TM)
            U[:] = random_like(U)
            F = TM.forward(U, F)
            V = TM.backward(F, V)
            assert allclose(V, U)

            fftp = fft.get_dealiased(padding_factor=1.5)

            #fft.destroy()

            #padding = 1.5
            #bases = []
            #for n in shape[:-1]:
            #    bases.append(FunctionSpace(n, 'F', dtype=typecode.upper(), padding_factor=padding))
            #bases.append(FunctionSpace(shape[-1], 'F', dtype=typecode, padding_factor=padding))

            #fft = TensorProductSpace(comm, bases, dtype=typecode)

            if comm.rank == 0:
                grid = [c.size for c in fftp.subcomm]
                print('grid:{} shape:{} typecode:{}'
                      .format(grid, shape, typecode))

            U = random_like(fftp.forward.input_array)
            F = fftp.forward(U)

            Fc = F.copy()
            V = fftp.backward(F)
            F = fftp.forward(V)
            assert allclose(F, Fc)

            # Alternative method
            fftp.backward.input_array[...] = F
            fftp.backward()
            fftp.forward()
            V = fftp.forward.output_array
            assert allclose(F, V)

            fftp.destroy()
            fft.destroy()