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thliebig / openEMS

openEMS is a free and open-source electromagnetic field solver using the EC-FDTD method.
http://openEMS.de
GNU General Public License v3.0
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Problem with FD values from probes #15

Closed georgmichel closed 8 years ago

georgmichel commented 8 years ago

When the 'Frequency' option is provided to AddProbe, the resulting frequency domain data is close, but not identical to the conjugate complex of the data which is calculated via ReadUI afterwards. The sign of the exponent in ProcessIntegral::Process line 161 is nevertheless in agreement with the octave definition of the Fourier transform. The resulting positive phase drift from AddProbe is not in agreement with the assumed definition of the Fourier transform, i.e. int(f(t)_exp(-2_pi_omega_f*t), dt) is the forward transform.

georgmichel commented 8 years ago

Sorry, my fault. I overlooked that fact that transposing a vector in Octave means also taking the conjugate complex of the vector to be transposed. openEMS and Octave agree (more or less) with their Fourier transform results.