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Getting more data after MC run directly in the Results table?

StephanWeber

Hi,

the ViVA calculator has some nice statistical functions, like average, stddev, skewness, kurtosis, and building more like Cpk or Jarque-Bera JB is not so difficult. But I struggle to get this not only in the calculator but really as output, e.g. to define a spec! E.g. we want Cpk>1.67 or  e.g. JB<3 for check for Gaussian data.

What works so far is this: 

I switch to Detailed table mode, select an output like Rsense or VoutDC, do a "plot across points", then I go to Viva and make "Send to Calculator", then I get an expression like swapSweep(Rsense "Design Points" "nom"), next I simply set x=swapSweep(Rsense "Design Points" "nom"). So it is no easy to get the mean and stddev and then to plot the Gaussian PDF of that fit.

However, I struggle to make that not only manually every time after the MC run but as output expression which would give a much higher automation. E.g. I want to see:

- The PDF plot for a fit for each MC analysis and my key outputs (I run MC vs VT corners)

- Also look for 5-sigma values

- Check if data is Gaussian, e.g. do also other fits like lognormal fit of JB is too large

- Or check at which corner the 5-sigma value is worst, etc.

This way I also do not need to plot Histograms etc. manually after each run.
His anybody done this before?

e.g. stddev(Rsense ?overall t) (with sweeps selected) works but skewness(Rsense ?overall t) (works in CIW!!) is changed to (skewness Rsense ?overall t)
same issue for kurtosis.

Are these Cadence-functions not registered in ADE?

Bye Stephan

  • StephanWeber
    in reply to Andrew Beckett

    Hi Andrew, 

    but can't we use a run plan, and use the pre-run script feature to create the additional desired ADE outputs, and after the run we see them in ADE Results table?

    That script could:

    Get all the  existing outputs
    And if e.g. a spec is set then add the add. outputs for stddevOutputname, skewnessOutputname, fits, etc.
    (using "meas across sweep" or even "across all" for get WC corner values)

    Bye Stephan

  • Andrew Beckett
    in reply to StephanWeber

    You can't add outputs in a run plan, so this approach won't work.

  • StephanWeber
    in reply to Andrew Beckett

    Can't we go for

    ocnxlAddOrUpdateOutput("Calibrated_ParamName" CalResult) 

    or (as workaround)

    ocnxlUpdatePointVariable("ParamName" sprintf( nil "%L" CalResult)) 

    Like in the trimming flow example?

    Bye Stephan

  • Andrew Beckett
    in reply to StephanWeber
    StephanWeber said:

    Can't we go for

    ocnxlAddOrUpdateOutput("Calibrated_ParamName" CalResult) 

    or (as workaround)

    ocnxlUpdatePointVariable("ParamName" sprintf( nil "%L" CalResult)) 

    Like in the trimming flow example?

    No. These are for use in the per-test pre-run script. A run plan has (potentially) multiple tests, and even if these worked there (which they don't AFAIK) you would need to be able to specify which test the output gets added to.

    There would be no point anyway; as I mentioned earlier on, you can already add several outputs in an OCEAN script measurement. What you can't do is have a regular expression output which magically adds multiple outputs, which is what you were proposing earlier.

    Andrew

  • StephanWeber
    in reply to Andrew Beckett

    I see axlAddOutputExpr could be a much better fit (it has all the parameters we need).

    Shouldn't this finally work?

  • StephanWeber
    in reply to Andrew Beckett

    OK, so it looks an export to CSV and make the automatic extensions for stat there, then reload is best. One advantage is that it would be permanently + manually editable in GUI. 

  • Andrew Beckett
    in reply to StephanWeber

    Or use the OCEAN script measurement that I repeatedly have mentioned.

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