From c607441717a9761f3f92aca6fa14a22b144aada3 Mon Sep 17 00:00:00 2001 From: Philip Eisenlohr Date: Tue, 22 May 2012 18:35:15 +0000 Subject: [PATCH] (likely) fixed a bug in the FFT-based geometry reconstruction. For (hopefully) correct math see Appendix B in paper. --- code/math.f90 | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/code/math.f90 b/code/math.f90 index c144647e3..23a6069de 100644 --- a/code/math.f90 +++ b/code/math.f90 @@ -3313,7 +3313,7 @@ subroutine deformed_fft(res,geomdim,defgrad_av,scaling,defgrad,coords) real(pReal), dimension(:,:,:,:), pointer :: coords_real complex(pReal), dimension(:,:,:,:), pointer :: coords_fourier ! other variables - integer(pInt) :: i, j, k, res1_red + integer(pInt) :: i, j, k, m, res1_red integer(pInt), dimension(3) :: k_s real(pReal), dimension(3) :: step, offset_coords, integrator @@ -3375,12 +3375,17 @@ subroutine deformed_fft(res,geomdim,defgrad_av,scaling,defgrad,coords) if(j > res(2)/2_pInt+1_pInt) k_s(2) = k_s(2)-res(2) do i = 1_pInt, res1_red k_s(1) = i-1_pInt - if(i/=1_pInt) coords_fourier(i,j,k,1:3) = coords_fourier(i,j,k,1:3)& ! substituting division by (on the fly calculated) xi * 2pi * img by multiplication with reversed img/real part - - defgrad_fourier(i,j,k,1:3,1)*cmplx(0.0_pReal,integrator(1)/real(k_s(1),pReal),pReal) - if(j/=1_pInt) coords_fourier(i,j,k,1:3) = coords_fourier(i,j,k,1:3)& - - defgrad_fourier(i,j,k,1:3,2)*cmplx(0.0_pReal,integrator(2)/real(k_s(2),pReal),pReal) - if(k/=1_pInt) coords_fourier(i,j,k,1:3) = coords_fourier(i,j,k,1:3)& - - defgrad_fourier(i,j,k,1:3,3)*cmplx(0.0_pReal,integrator(3)/real(k_s(3),pReal),pReal) + do m = 1_pInt,3_pInt + coords_fourier(i,j,k,m) = sum(defgrad_fourier(i,j,k,m,1:3)*cmplx(0.0_pReal,real(k_s,pReal)*integrator,pReal)) + enddo + if (k_s(3) /= 0_pInt .or. k_s(2) /= 0_pInt .or. k_s(1) /= 0_pInt) & + coords_fourier(i,j,k,1:3) = coords_fourier(i,j,k,1:3) / real(-sum(k_s*k_s),pReal) +! if(i/=1_pInt) coords_fourier(i,j,k,1:3) = coords_fourier(i,j,k,1:3)& ! substituting division by (on the fly calculated) xi * 2pi * img by multiplication with reversed img/real part +! - defgrad_fourier(i,j,k,1:3,1)*cmplx(0.0_pReal,integrator(1)/real(k_s(1),pReal),pReal) +! if(j/=1_pInt) coords_fourier(i,j,k,1:3) = coords_fourier(i,j,k,1:3)& +! - defgrad_fourier(i,j,k,1:3,2)*cmplx(0.0_pReal,integrator(2)/real(k_s(2),pReal),pReal) +! if(k/=1_pInt) coords_fourier(i,j,k,1:3) = coords_fourier(i,j,k,1:3)& +! - defgrad_fourier(i,j,k,1:3,3)*cmplx(0.0_pReal,integrator(3)/real(k_s(3),pReal),pReal) enddo; enddo; enddo call fftw_execute_dft_c2r(fftw_back,coords_fourier,coords_real)