Example #1
0
def test_FFT2(FFT2):
    if FFT2.rank == 0:
        A = random((N, N)).astype(FFT2.float)

    else:
        A = zeros((N, N), dtype=FFT2.float)

    FFT2.comm.Bcast(A, root=0)
    a = zeros(FFT2.real_shape(), dtype=FFT2.float)
    c = zeros(FFT2.complex_shape(), dtype=FFT2.complex)
    a[:] = A[FFT2.real_local_slice()]
    c = FFT2.fft2(a, c)
    B2 = rfft2(A, axes=(0, 1))
    assert allclose(c, B2[FFT2.complex_local_slice()])
    a = FFT2.ifft2(c, a)
    assert allclose(a, A[FFT2.real_local_slice()], 5e-7, 5e-7)
Example #2
0
 def fft(self, u, fu):
     """Fast Fourier transform of y and z"""
     # Intermediate work arrays
     Uc_mpi = self.work_arrays[((self.num_processes, self.Np[0], self.Np[1],
                                 self.Nf), self.complex, 0)]
     Uc_hatT = self.work_arrays[(self.complex_shape_T(), self.complex, 0)]
     Uc_hatT = rfft2(u,
                     Uc_hatT,
                     axes=(1, 2),
                     threads=self.threads,
                     planner_effort=self.planner_effort['rfft2'])
     Uc_mpi[:] = rollaxis(
         Uc_hatT.reshape(self.Np[0], self.num_processes, self.Np[1],
                         self.Nf), 1)
     self.comm.Alltoall([Uc_mpi, self.mpitype], [fu, self.mpitype])
     return fu
Example #3
0
def test_FFT2(FFT2):
    N = FFT2.N
    if FFT2.rank == 0:
        A = random(N).astype(FFT2.float)

    else:
        A = zeros(N, dtype=FFT2.float)

    atol, rtol = (1e-10, 1e-8) if FFT2.float is float64 else (5e-7, 1e-4)
    FFT2.comm.Bcast(A, root=0)
    a = zeros(FFT2.real_shape(), dtype=FFT2.float)
    c = zeros(FFT2.complex_shape(), dtype=FFT2.complex)
    a[:] = A[FFT2.real_local_slice()]
    c = FFT2.fft2(a, c)
    B2 = zeros(FFT2.global_complex_shape(), dtype=FFT2.complex)
    B2 = rfft2(A, B2, axes=(0, 1))
    assert allclose(c, B2[FFT2.complex_local_slice()], rtol, atol)
    a = FFT2.ifft2(c, a)
    assert allclose(a, A[FFT2.real_local_slice()], rtol, atol)
Example #4
0
    def _forward(self, u, fu, fun, dealias=None):

        # Intermediate work arrays
        Uc_hat = self.work_arrays[(self.complex_shape(), self.complex, 0)]

        if self.num_processes == 1:

            if not dealias == '3/2-rule':
                assert u.shape == self.real_shape()

                Uc_hat = rfft2(u,
                               Uc_hat,
                               axes=(1, 2),
                               threads=self.threads,
                               planner_effort=self.planner_effort['rfft2'])
                fu = fun(Uc_hat, fu)

            else:
                if not self.dealias_cheb:
                    Upad_hat = self.work_arrays[(self.complex_shape_padded(),
                                                 self.complex, 0, False)]
                    Upad_hat_z = self.work_arrays[((self.N[0],
                                                    int(self.padsize *
                                                        self.N[1]), self.Nf),
                                                   self.complex, 0, False)]

                    Upad_hat = rfft(u,
                                    Upad_hat,
                                    axis=2,
                                    threads=self.threads,
                                    planner_effort=self.planner_effort['rfft'])
                    Upad_hat_z = SlabShen_R2C.copy_from_padded(
                        Upad_hat, Upad_hat_z, self.N, 2)
                    Upad_hat_z[:] = fft(
                        Upad_hat_z,
                        axis=1,
                        overwrite_input=True,
                        threads=self.threads,
                        planner_effort=self.planner_effort['fft'])
                    Uc_hat = SlabShen_R2C.copy_from_padded(
                        Upad_hat_z, Uc_hat, self.N, 1)
                    fu = fun(Uc_hat / self.padsize**2, fu)
                else:
                    # Intermediate work arrays required for transform
                    Upad_hat = self.work_arrays[(self.complex_shape_padded_0(),
                                                 self.complex, 0, False)]
                    Upad_hat0 = self.work_arrays[(
                        self.complex_shape_padded_0(), self.complex, 1, False)]
                    Upad_hat2 = self.work_arrays[(
                        self.complex_shape_padded_2(), self.complex, 0, False)]
                    Upad_hat3 = self.work_arrays[(
                        self.complex_shape_padded_3(), self.complex, 0, False)]

                    # Do ffts and truncation in the padded y and z directions
                    Upad_hat3 = rfft(
                        u,
                        Upad_hat3,
                        axis=2,
                        threads=self.threads,
                        planner_effort=self.planner_effort['rfft'])
                    Upad_hat2 = SlabShen_R2C.copy_from_padded(
                        Upad_hat3, Upad_hat2, self.N, 2)
                    Upad_hat2[:] = fft(
                        Upad_hat2,
                        axis=1,
                        threads=self.threads,
                        planner_effort=self.planner_effort['fft'])
                    Upad_hat = SlabShen_R2C.copy_from_padded(
                        Upad_hat2, Upad_hat, self.N, 1)

                    # Perform fst of data in x-direction
                    Upad_hat0 = fun(Upad_hat, Upad_hat0)

                    # Truncate to original complex shape
                    fu[:] = Upad_hat0[:self.N[0]] / self.padsize**2
            return fu

        if not dealias == '3/2-rule':

            Uc_hatT = self.work_arrays[(self.complex_shape_T(), self.complex,
                                        0, False)]
            Uc_hat = self.work_arrays[(fu, 0, False)]

            if self.communication == 'Alltoall':
                #Uc_mpi  = Uc_hat.reshape((self.num_processes, self.Np[0], self.Np[1], self.Nf))
                #Uc_hatT = rfft2(u, Uc_hatT, axes=(1,2), threads=self.threads, planner_effort=self.planner_effort['rfft2'])
                #Uc_mpi[:] = rollaxis(Uc_hatT.reshape(self.Np[0], self.num_processes, self.Np[1], self.Nf), 1)
                #self.comm.Alltoall(MPI.IN_PLACE, [Uc_hat, self.mpitype])

                # Intermediate work array required for transform
                U_mpi = self.work_arrays[((self.num_processes, self.Np[0],
                                           self.Np[1], self.Nf), self.complex,
                                          0, False)]

                # Do 2 ffts in y-z directions on owned data
                Uc_hatT = rfft2(u,
                                Uc_hatT,
                                axes=(1, 2),
                                threads=self.threads,
                                planner_effort=self.planner_effort['rfft2'])

                #Transform data to align with x-direction
                U_mpi[:] = rollaxis(
                    Uc_hatT.reshape(self.Np[0], self.num_processes, self.Np[1],
                                    self.Nf), 1)

                #Communicate all values
                self.comm.Alltoall([U_mpi, self.mpitype],
                                   [Uc_hat, self.mpitype])

            elif self.communication == 'Alltoallw':
                if not self._subarraysA:
                    self._subarraysA, self._subarraysB, self._counts_displs = self.get_subarrays(
                    )

                # Do 2 ffts in y-z directions on owned data
                Uc_hatT = rfft2(u,
                                Uc_hatT,
                                axes=(1, 2),
                                threads=self.threads,
                                planner_effort=self.planner_effort['rfft2'])

                self.comm.Alltoallw(
                    [Uc_hatT, self._counts_displs, self._subarraysB],
                    [Uc_hat, self._counts_displs, self._subarraysA])

            fu = fun(Uc_hat, fu)

        else:
            Uc_hatT = self.work_arrays[(self.complex_shape_T(), self.complex,
                                        0, False)]

            if not self.dealias_cheb:
                Upad_hatT = self.work_arrays[(self.complex_shape_padded_T(),
                                              self.complex, 0, False)]
                Upad_hat_z = self.work_arrays[((self.Np[0],
                                                int(self.padsize * self.N[1]),
                                                self.Nf), self.complex, 0,
                                               False)]

                Upad_hatT = rfft(u,
                                 Upad_hatT,
                                 axis=2,
                                 threads=self.threads,
                                 planner_effort=self.planner_effort['rfft'])
                Upad_hat_z = SlabShen_R2C.copy_from_padded(
                    Upad_hatT, Upad_hat_z, self.N, 2)
                Upad_hat_z[:] = fft(Upad_hat_z,
                                    axis=1,
                                    threads=self.threads,
                                    planner_effort=self.planner_effort['fft'])
                Uc_hatT = SlabShen_R2C.copy_from_padded(
                    Upad_hat_z, Uc_hatT, self.N, 1)

                if self.communication == 'Alltoall':
                    #Uc_mpi  = Uc_hat.reshape((self.num_processes, self.Np[0], self.Np[1], self.Nf))
                    #Uc_mpi[:] = rollaxis(Uc_hatT.reshape(self.Np[0], self.num_processes, self.Np[1], self.Nf), 1)
                    #self.comm.Alltoall(MPI.IN_PLACE, [Uc_hat, self.mpitype])

                    Uc_mpi = self.work_arrays[((self.num_processes, self.Np[0],
                                                self.Np[1], self.Nf),
                                               self.complex, 2, False)]
                    Uc_mpi[:] = rollaxis(
                        Uc_hatT.reshape(self.Np[0], self.num_processes,
                                        self.Np[1], self.Nf), 1)
                    self.comm.Alltoall([Uc_mpi, self.mpitype],
                                       [Uc_hat, self.mpitype])

                elif self.communication == 'Alltoallw':
                    if not self._subarraysA:
                        self._subarraysA, self._subarraysB, self._counts_displs = self.get_subarrays(
                        )
                    self.comm.Alltoallw(
                        [Uc_hatT, self._counts_displs, self._subarraysB],
                        [Uc_hat, self._counts_displs, self._subarraysA])

                fu = fun(Uc_hat / self.padsize**2, fu)

            else:
                assert self.num_processes <= self.N[
                    0] / 2, "Number of processors cannot be larger than N[0]/2 for 3/2-rule"
                assert u.shape == self.real_shape_padded()

                # Intermediate work arrays required for transform
                Upad_hat = self.work_arrays[(self.complex_shape_padded_0(),
                                             self.complex, 0, False)]
                Upad_hat0 = self.work_arrays[(self.complex_shape_padded_0(),
                                              self.complex, 1, False)]
                Upad_hat1 = self.work_arrays[(self.complex_shape_padded_1(),
                                              self.complex, 0, False)]
                Upad_hat2 = self.work_arrays[(self.complex_shape_padded_2(),
                                              self.complex, 0, False)]
                Upad_hat3 = self.work_arrays[(self.complex_shape_padded_3(),
                                              self.complex, 0, False)]

                # Do ffts and truncation in the padded y and z directions
                Upad_hat3 = rfft(u,
                                 Upad_hat3,
                                 axis=2,
                                 threads=self.threads,
                                 planner_effort=self.planner_effort['rfft'])
                Upad_hat2 = SlabShen_R2C.copy_from_padded(
                    Upad_hat3, Upad_hat2, self.N, 2)
                Upad_hat2[:] = fft(Upad_hat2,
                                   axis=1,
                                   threads=self.threads,
                                   planner_effort=self.planner_effort['fft'])
                Upad_hat1 = SlabShen_R2C.copy_from_padded(
                    Upad_hat2, Upad_hat1, self.N, 1)

                if self.communication == 'Alltoall':
                    # Transpose and commuincate data
                    U_mpi = Upad_hat.reshape(self.complex_shape_padded_0_I())
                    U_mpi[:] = rollaxis(
                        Upad_hat1.reshape(self.complex_shape_padded_I()), 1)
                    self.comm.Alltoall(MPI.IN_PLACE, [Upad_hat, self.mpitype])

                elif self.communication == 'Alltoallw':
                    if not self._subarraysA_pad:
                        self._subarraysA_pad, self._subarraysB_pad, self._counts_displs = self.get_subarrays(
                            padsize=self.padsize)

                    self.comm.Alltoallw(
                        [Upad_hat1, self._counts_displs, self._subarraysB_pad],
                        [Upad_hat, self._counts_displs, self._subarraysA_pad])

                # Perform fst of data in x-direction
                Upad_hat0 = fun(Upad_hat, Upad_hat0)

                # Truncate to original complex shape
                fu[:] = Upad_hat0[:self.N[0]] / self.padsize**2

        return fu