diff options
| -rw-r--r-- | src/navier-stokes.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/src/navier-stokes.c b/src/navier-stokes.c index 89bfbbd..e553022 100644 --- a/src/navier-stokes.c +++ b/src/navier-stokes.c @@ -495,7 +495,8 @@ int ns_T( fftw_execute(fft2.fft_plan); // write to ifft for(i=0;i<N1*N2;i++){ - ifft.fft[i]=fft1.fft[i]*fft2.fft[i]; + // control numerical truncation by taking imaginary part (fft1 and fft2 should be purely imaginary) + ifft.fft[i]=-(__imag__ fft1.fft[i])*(__imag__ fft2.fft[i]); } // F(py/|p|*u)*F(qx*|q|*u) @@ -519,7 +520,8 @@ int ns_T( fftw_execute(fft2.fft_plan); // write to ifft for(i=0;i<N1*N2;i++){ - ifft.fft[i]=ifft.fft[i]-fft1.fft[i]*fft2.fft[i]; + // control numerical truncation by taking imaginary part (fft1 and fft2 should be purely imaginary) + ifft.fft[i]=ifft.fft[i]+(__imag__ fft1.fft[i])*(__imag__ fft2.fft[i]); } // inverse fft |