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Displaying waveform from Skill script as expression

shlomo34

I can create and plot a waveform within a Skill script, but when I try to save the waveform as a Maestro measurement, it cannot then be plotted.

Details:

I have a Skill function which creates, plots, and returns a waveform. Selected lines from function:

jitter = drCreateWaveform( drCreateVec( `double vectorToList(jitter_x) ) drCreateVec( `double vectorToList(jitter_y) ))
plot(jitter ?expr list( "jitter" ))
return( jitter )

In my Maestro outputs I run this function and store its output as expression "jit1". As I run the function, the "plot" command works correctly and shows a waveform plot.

In Maestro simulation results, "jit1" appears as a waveform. But when I doubleclick this waveform and open it as a plot, it returns an error:

ERROR (ADE-1057): Could not evaluate expression
Name:'jit1'
Expression:'fxn_jitter("/net0")'
because of the following error(s)
("ilGetString" 0 t nil ("*Error* ilGetString: arg must be symbol or string" (1.019251e-09 1.088974e-09 1.158697e-09 1.22842e-09 1.298143e-09...


What is going wrong?

Parents

  • I suspect the issue is that you're not dealing with family data in the function. Your function should also not plot anything, since that will interfere with the ADE plotting mechanism (and won't work with plotting templates, data sheets and so on). In order to understand this, I'd probably need to see the entire function, not just pieces of it.

    If you can't post that here, would it be OK if I contact you directly since I have your contact details because of the duplicate CCR that was filed on your behalf the other day? I can then create a case and we can follow it up that way.

    Regards,

    Andrew.

  • in reply to Andrew Beckett

    Please contact me and we can add the postmortem here when we're done. Thanks :)

  • in reply to shlomo34

    As promised, here's a summary of the solution.

    As I suspected, it was indeed that the code didn't handle family data. Whilst much of the time calculator functions called from ADE Explorer/Assembler (when they return scalar values) only see single results and not family data, if they return a waveform the expression gets called again when you plot the results from the ADE UI. This then sees the family of results, which allows the plot to indicate which sweep points it's against, but does mean that the function needs to handle family data.

    I solved it in this case by introducing a function inside which got passed a waveform object, and then followed the usual pattern:

    cond(

       (drIsWaveform(sig)
           ; handle single signals
       )
       (famIsFamily(sig)
            famMap('theFunc sig arg1 arg2 arg3 …)
       )
       (t
            error("report an error because it's an unknown argument")
       )
    )

    The idea is that the function calls a function which maps over the family, calling the function for each member of the family, and then reassembles the results.

    You'll see similar code in many of my calculator functions, such as those found in this forum, but also at Custom IC Calculator SKILL Function Library.

    Andrew

Reply
  • in reply to shlomo34

    As promised, here's a summary of the solution.

    As I suspected, it was indeed that the code didn't handle family data. Whilst much of the time calculator functions called from ADE Explorer/Assembler (when they return scalar values) only see single results and not family data, if they return a waveform the expression gets called again when you plot the results from the ADE UI. This then sees the family of results, which allows the plot to indicate which sweep points it's against, but does mean that the function needs to handle family data.

    I solved it in this case by introducing a function inside which got passed a waveform object, and then followed the usual pattern:

    cond(

       (drIsWaveform(sig)
           ; handle single signals
       )
       (famIsFamily(sig)
            famMap('theFunc sig arg1 arg2 arg3 …)
       )
       (t
            error("report an error because it's an unknown argument")
       )
    )

    The idea is that the function calls a function which maps over the family, calling the function for each member of the family, and then reassembles the results.

    You'll see similar code in many of my calculator functions, such as those found in this forum, but also at Custom IC Calculator SKILL Function Library.

    Andrew

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