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Sweep over frequency and use frequency for calculations

itos

Hello,


I have the problem that I want to sweep over frequency (for example with pss) and then use the frequency itself in calculations. The problem: Not only the results traces are a vector but also the frequency variable itself! In the calculations, I would like to use the single frequency (scalar) as argument, not the entire vector.

Example:

  • Sweep over input frequency fin
  • Expression: dB20((thd(v("/vod" ?result "pss_td") 0 (1 / VAR("fin")) VAR("NDFT") VAR("fin")) / 100))
  • Plot this expression vs. fin

ADE L accepts this expression but the results are wrong (compared with just a single run). I assume the reason is it supplies the entire array of fin when I use VAR("fin"). instead only the one from the current run.

It's a little intricate ... any way around here?

  • itos
    I just wanted to push this a bit because this really happens very often. It's not limited to frequencies but to variable which is swept and is used as an input to a cadence function that's supposed to be a scalar ... Even if someone tells me it's not possible helps already ...
  • Andrew Beckett

    If it was urgent, you should go to customer support.

    Without seeing the details of the setup, it's hard to know, but you might need to use something like:

    dB20((famMap('thd v("/vod" ?result "pss_td") 0 (1 / VAR("fin")) VAR("NDFT") VAR("fin")) / 100))

    The famMap could then handle the expansion of the sweeps. Not certain though without a testcase to try it out (and I don't really have time to put one together).

    Regards,

    Andrew.

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