Question about the sequence of calculations

[d5244af6a0]

Hello everyone.
I'm using ngspice as a backend; Qucs-s 25.
As a result of transient analysis, I get voltage and current vectors. I get voltage "U" and current "I" vectors (in the ngspice console, this looks slightly different, but doesn't affect the essence of the question). Next, I create a block with a nutmeg
script, in which I calculate a new power vector "P" by multiplying the "U" and "I" vectors. In the ngspice console, I see the desired resulting "P" vector.
Next, I want to perform a harmonic Fourier analysis and insert the corresponding simulation into the scheme. In the listing, I see a call to the "fourier" command within ngspice.
However, Qucs-s inserts the call to the "fourier" command BEFORE the nutmeg script. At this point, the "P" vector hasn't yet been generated.
How do I correctly run the Fourier transform after calculating the auxiliary vectors?
Here is a fragment of the ngspice listing:
27 : .control
28 : tran 3.92157e-11 1e-06 9.9e-07
29 : set nfreqs=5
30 : fourier 100meg pk > spice4qucs.four1.four
31 : let pk=i(vik)*v(uk)
32 : .endc
Thanks

[jgardona]

Hello, why not use the "nutmeg equation" to calculate the power? Nutmeg equations run "AFTER" the nscripts, while, params runs "BEFORE" the nscripts. Nutmeg scripts always run at the meddle of pipeline.

[d5244af6a0]

Thank you. Of course, I used the nutmeg equation. As a result, the Fourier transform is run before the additional vector is calculated (part of the ngspice script listing is shown in the original message). Is it possible to run the Fourier transform after the additional vectors are calculated?

[jgardona]

Thats strange. Have you tried call fourier analysis from a nutmeg script?

[d5244af6a0]

Thanks for your response. Of course, I tried it: I inserted the line "fourier 100meg pk" - the nutmeg block silently rejects it, as if it didn't exist

[jgardona]

@d5244af6a0 give a look:

.fourier will only see the circuit netlist. You need to call a nutmeg function (MAG, FFT...).

https://ngspice.sourceforge.io/docs/ngspice-html-manual/manual.xhtml#subsec_fft__fast_Fourier