Power systems engineer. 18 years in consulting. Currently pursuing PhD.

Thanks for taking the time to type this up, twice apparently.  Much appreciated.  The examples help a lot.  I'll be working through this today.  
Thank you.  That is very helpful.  I will review this information in more detail next week, but two questions come to mind:  1) speed is important in my code...
Negative - power systems.. as in high voltage transmission line electromagnetics.  I don't work in controls, but am aware that much DSP is involved in that area...
And thanks to other folks who posted - those conversations helped get me oriented.
Excellent!  Thanks for the help.  I'm in power systems and never expected to delve into the DSP realm. However, it has been very interesting.  It seems the...
Ok. That makes sense and I was able to get things to work.  I had to experiment a bit and I'm not sure I quite matched your description above, but the attached...
Do you mean:  ...You should be able to map the DFT bins 0 to N/2 on your domain of 0 to 3, then N/2 to N on your domain of -3 to 0...?
I reviewed your answers in the other forums and I think they do relate to the specific concepts I am confused about.  Taking a step back, attached is a better...
Thanks.  I think I see what you are getting at. A lot of good responses on this forum. I need to let all this information simmer and sink in.
Fair enough.  Poorly worded on my part.  Plot A is spectrum plot.  Thanks for the link.  I will review.  It looks helpul at first glance.
Adding to this - the integration method is quite slow which is why I'm trying to do this by discrete methods.  When it is all said an done I would like to understand...
I can get this as well, but this is the result obtained using the typical transform pair involving exp(i*2*pi*gamma*t).  Also, the imaginary component of the...
I obtained B by inverse Fourier transform of A.  My code implements what I'm calling the continuous form because it integrates the original continuous frequency...
Post above in a reply to Platybek...signals.xlsx
The problem is related to electric field analysis. I have confirmed through independent means that figure B is correct from a spatial point of view. The calculus...
Comments:OK, so you started with curves A and by algebra and calculus you computed curves B which are the time response (you call it a spatial response, makes no...
This is the data for all four plots.  Plots without data for the horizontal axes are just indexed based on array position.  Thanks for the help.signals.xlsx
The attached pdf has supplementary info.  I try a different way of asking the question and I include some code snippets with examples of their function calls. ...
Thank you for the reply.  The code is written in Julia and all numbers are complex, though as you say, the imaginary part in the spatial domain is zero (or very-very...
I have a continuous function that defines a 1D frequency domain signal.  Plot A in the attached image shows the real and imaginary portions of the sampled signal...

Re: Inverse FFT of a Sampled Frequency Domain Function

Reply posted 9 months ago (01/30/2020)
My data is in Cartesian so it sounds like I need to create a complex conjugate array, reverse the order and prepend to the existing array.  Thanks!

Re: Inverse FFT of a Sampled Frequency Domain Function

Reply posted 9 months ago (01/30/2020)
Thanks!  If I proceed to process the input array directly, am I correct in my understanding that only the first half of the resulting time array is "useful"?
Pardon the basic nature of this question.  DSP is not my area of expertise.  I have an equation for a continuous frequency domain function - I'll call it Z(jω)...

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