plane waves have known solutions

This commit is contained in:
Martin Diehl 2022-11-26 11:58:36 +01:00
parent 6be1d43dc6
commit 39157b75b7
2 changed files with 54 additions and 14 deletions

View File

@ -103,10 +103,10 @@ def divergence(size: _FloatSequence,
k_s = _ks(size,f.shape[:3],True)
f_fourier = _np.fft.rfftn(f,axes=(0,1,2))
div_ = (_np.einsum('ijkl,ijkl ->ijk', k_s,f_fourier)*2.0j*_np.pi if n == 3 else # vector, 3 -> 1
divergence_ = (_np.einsum('ijkl,ijkl ->ijk', k_s,f_fourier)*2.0j*_np.pi if n == 3 else # vector, 3 -> 1
_np.einsum('ijkm,ijklm->ijkl',k_s,f_fourier)*2.0j*_np.pi) # tensor, 3x3 -> 3
return _np.fft.irfftn(div_,axes=(0,1,2),s=f.shape[:3])
return _np.fft.irfftn(divergence_,axes=(0,1,2),s=f.shape[:3])
def gradient(size: _FloatSequence,
@ -124,17 +124,17 @@ def gradient(size: _FloatSequence,
Returns
-------
f : numpy.ndarray, shape (:,:,:,3) or (:,:,:,3,3)
Divergence of f.
Gradient of f.
"""
n = _np.prod(f.shape[3:])
k_s = _ks(size,f.shape[:3],True)
f_fourier = _np.fft.rfftn(f,axes=(0,1,2))
grad_ = (_np.einsum('ijkl,ijkm->ijkm', f_fourier,k_s)*2.0j*_np.pi if n == 1 else # scalar, 1 -> 3
gradient_ = (_np.einsum('ijkl,ijkm->ijkm', f_fourier,k_s)*2.0j*_np.pi if n == 1 else # scalar, 1 -> 3
_np.einsum('ijkl,ijkm->ijklm',f_fourier,k_s)*2.0j*_np.pi) # vector, 3 -> 3x3
return _np.fft.irfftn(grad_,axes=(0,1,2),s=f.shape[:3])
return _np.fft.irfftn(gradient_,axes=(0,1,2),s=f.shape[:3])
def coordinates0_point(cells: _IntSequence,

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@ -763,7 +763,7 @@ function utilities_scalarGradient(field) result(grad)
scalarField_real(1:cells(1), 1:cells(2),1:cells3) = field
call fftw_mpi_execute_dft_r2c(planScalarForth,scalarField_real,scalarField_fourier)
do j = 1, cells2; do k = 1, cells(3); do i = 1,cells1Red
vectorField_fourier(1:3,i,k,j) = scalarField_fourier(i,k,j)*xi1st(1:3,i,k,j) ! ToDo: no -conjg?
vectorField_fourier(1:3,i,k,j) = scalarField_fourier(i,k,j)*xi1st(1:3,i,k,j)
end do; end do; end do
call fftw_mpi_execute_dft_c2r(planVectorBack,vectorField_fourier,vectorField_real)
grad = vectorField_real(1:3,1:cells(1),1:cells(2),1:cells3)*wgt
@ -784,7 +784,7 @@ function utilities_vectorDivergence(field) result(div)
vectorField_real(1:3,1:cells(1), 1:cells(2),1:cells3) = field
call fftw_mpi_execute_dft_r2c(planVectorForth,vectorField_real,vectorField_fourier)
scalarField_fourier(1:cells1Red,1:cells(3),1:cells2) = sum(vectorField_fourier(1:3,1:cells1Red,1:cells(3),1:cells2) &
*conjg(-xi1st),1)
*conjg(-xi1st),1) ! ToDo: use "xi1st" instead of "conjg(-xi1st)"?
call fftw_mpi_execute_dft_c2r(planScalarBack,scalarField_fourier,scalarField_real)
div = scalarField_real(1:cells(1),1:cells(2),1:cells3)*wgt
@ -930,7 +930,7 @@ end function utilities_forwardField
!--------------------------------------------------------------------------------------------------
!> @brief calculates filter for fourier convolution depending on type given in numerics.config
!> @brief Calculate Filter for Fourier convolution.
!> @details this is the full operator to calculate derivatives, i.e. 2 \pi i k for the
! standard approach
!--------------------------------------------------------------------------------------------------
@ -1171,14 +1171,54 @@ subroutine selfTest()
if (err_MPI /= 0_MPI_INTEGER_KIND) error stop 'MPI error'
scalarField_real_ = r(1,1)
if (maxval(abs(utilities_scalarGradient(scalarField_real_)))>5.0e-15_pReal) error stop 'grad constant'
if (maxval(abs(utilities_scalarGradient(scalarField_real_)))>5.0e-9_pReal) error stop 'grad constant'
vectorField_real_ = spread(spread(spread(r(1,:),2,cells(1)),3,cells(2)),4,cells3)
if (maxval(abs(utilities_vectorDivergence(vectorField_real_)))>5.0e-15_pReal) error stop 'div constant'
if (maxval(abs(utilities_vectorDivergence(vectorField_real_)))>5.0e-9_pReal) error stop 'div constant'
tensorField_real_ = spread(spread(spread(r,3,cells(1)),4,cells(2)),5,cells3)
if (utilities_divergenceRMS(tensorField_real_)>5.0e-15_pReal) error stop 'RMS div constant'
if (utilities_curlRMS(tensorField_real_)>5.0e-15_pReal) error stop 'RMS curl constant'
if (utilities_divergenceRMS(tensorField_real_)>5.0e-14_pReal) error stop 'RMS div constant'
if (utilities_curlRMS(tensorField_real_)>5.0e-14_pReal) error stop 'RMS curl constant'
if (cells(1) > 2 .and. spectral_derivative_ID == DERIVATIVE_CONTINUOUS_ID) then
scalarField_real_ = spread(spread(planeCosine(cells(1)),2,cells(2)),3,cells3)
vectorField_real_ = utilities_scalarGradient(scalarField_real_)/TAU*geomSize(1)
scalarField_real_ = -spread(spread(planeSine (cells(1)),2,cells(2)),3,cells3)
if (maxval(abs(vectorField_real_(1,:,:,:) - scalarField_real_))>5.0e-14_pReal) error stop 'grad cosine'
scalarField_real_ = spread(spread(planeSine (cells(1)),2,cells(2)),3,cells3)
vectorField_real_ = utilities_scalarGradient(scalarField_real_)/TAU*geomSize(1)
scalarField_real_ = spread(spread(planeCosine(cells(1)),2,cells(2)),3,cells3)
if (maxval(abs(vectorField_real_(1,:,:,:) - scalarField_real_))>5.0e-14_pReal) error stop 'grad sine'
vectorField_real_(2:3,:,:,:) = 0.0_pReal
vectorField_real_(1,:,:,:) = spread(spread(planeCosine(cells(1)),2,cells(2)),3,cells3)
scalarField_real_ = utilities_vectorDivergence(vectorField_real_)/TAU*geomSize(1)
vectorField_real_(1,:,:,:) =-spread(spread(planeSine( cells(1)),2,cells(2)),3,cells3)
if (maxval(abs(vectorField_real_(1,:,:,:) - scalarField_real_))>5.0e-14_pReal) error stop 'div cosine'
vectorField_real_(2:3,:,:,:) = 0.0_pReal
vectorField_real_(1,:,:,:) = spread(spread(planeSine( cells(1)),2,cells(2)),3,cells3)
scalarField_real_ = utilities_vectorDivergence(vectorField_real_)/TAU*geomSize(1)
vectorField_real_(1,:,:,:) = spread(spread(planeCosine(cells(1)),2,cells(2)),3,cells3)
if (maxval(abs(vectorField_real_(1,:,:,:) - scalarField_real_))>5.0e-14_pReal) error stop 'div sine'
end if
contains
function planeCosine(n)
integer, intent(in) :: n
real(pReal), dimension(n) :: planeCosine
planeCosine = cos(real(math_range(n),pReal)/real(n,pReal)*TAU-TAU/real(n*2,pReal))
end function planeCosine
function planeSine(n)
integer, intent(in) :: n
real(pReal), dimension(n) :: planeSine
planeSine = sin(real(math_range(n),pReal)/real(n,pReal)*TAU-TAU/real(n*2,pReal))
end function planeSine
end subroutine selfTest