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subgold

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Questions about MonteCarlo simulation in ADE
Jul 17^th, 2009, 8:33am

When I run the MonteCarlo simulation, there is a list of all the expressions in the window "Analog Statistical Analysis", which I want to evaluate.

After the MonteCarlo simulation is finished, i want to plot the histogram by the menu "result"-->"plot"-->"histogram" from the window "Analog Statistical Analysis".

However, many expressions are missing in the histogram dialogue window. (I checked the results directory, every run has successfully completed). How to retrive and plot these expressions?

Also, although all the simulation results are saved, it is not possible to change or add any expressions in the the "Analog Statistical Analysis" window (the expression is changed or added, but the histogram results are always the same).

Does anybody know the solution to these issues?

Thanks in advance.

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Andrew Beckett

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Re: Questions about MonteCarlo simulation in ADE
Reply #1 - Jul 20^th, 2009, 5:16am

I don't know why they would be missing, unless there was a problem with the evaluation of the expressions. This would show up in the Simulation->Output Log output. They'd also not appear if the calculations do not result in scalar values - i.e. if it's a calculation that produces a waveform for each point in the monte carlo sweep, you can't plot a histogram of that.

If you have done a "save data between runs to allow family plots", you can then add or modify any expressions on the Monte Carlo form, and then you need to do Results->Evaluate Expressions to re-calculate the scalar values at each time point. Having done that, you can then plot the histograms of the new or updated expressions.

Regards,

Andrew.

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subgold

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Re: Questions about MonteCarlo simulation in ADE
Reply #2 - Jul 20^th, 2009, 1:54pm

Andrew Beckett wrote on Jul 20^th, 2009, 5:16am:

I don't know why they would be missing, unless there was a problem with the evaluation of the expressions. This would show up in the Simulation->Output Log output. They'd also not appear if the calculations do not result in scalar values - i.e. if it's a calculation that produces a waveform for each point in the monte carlo sweep, you can't plot a histogram of that.

If you have done �a "save data between runs to allow family plots", you can then add or modify any expressions on the Monte Carlo form, and then you need to do Results->Evaluate Expressions to re-calculate the scalar values at each time point. Having done that, you can then plot the histograms of the new or updated expressions.

Regards,

Andrew.

thanks for the reply. actually i think the evaluation of the expressions should be fine, otherwise the montecarlo simulation would even not start. i also selected the "save data between runs to allow family plots" option.

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Andrew Beckett

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Re: Questions about MonteCarlo simulation in ADE
Reply #3 - Jul 20^th, 2009, 2:31pm

Actually it will only stop if they fail on the nominal run. Also, if the expressions are waveforms, you won't get histograms.

And what I said about doing Results->Evaluate Expressions still applies if you modify the expressions or add new ones.

Take a look in the mcparams and mcdata files in the monte dir alongside the netlist and psf dir, and see whether the parameter names have ended up in the scalar data file that is produced.

Regards,

Andrew.

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subgold

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Re: Questions about MonteCarlo simulation in ADE
Reply #4 - Jul 21^st, 2009, 5:10am

Andrew Beckett wrote on Jul 20^th, 2009, 2:31pm:

Actually it will only stop if they fail on the nominal run. Also, if the expressions are waveforms, you won't get histograms.

And what I said about doing Results->Evaluate Expressions still applies if you modify the expressions or add new ones.

Take a look in the mcparams and mcdata files in the monte dir alongside the netlist and psf dir, and see whether the parameter names have ended up in the scalar data file that is produced.

Regards,

Andrew.

hi, i dont have waveform expressions, all of them are scalar.

what i did was exactly what you said, but the "adding expression" and "Results->Evaluate Expressions" thing still doesn't work. the new expression shows up in the mcparam file, but its results are not in mcdata file, and cannot be found by "Results->Plot->histogram". if i reload the results by "Results->select...", then the new expression can be found by "Results->Plot->histogram", but still not in the mcdata file, so it still can not be ploted. if i do "Results->Evaluate Expressions" after the reload, i get the following error:

*Error* _gets: argument #1 should be an I/O port (type template = "p") - nil

but thanks anyway for your patience.

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Andrew Beckett Senior Fellow Offline Life, don't talk to me about Life... Posts: 1742 Bracknell, UK	Re: Questions about MonteCarlo simulation in ADE Reply #5 - Jul 21^st, 2009, 6:12am Sounds very odd. What subversion of the IC tools are you using? Type: getVersion(t) in the CIW, and let me know what it says. Regards, Andrew.
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subgold Community Member Offline Posts: 97	Re: Questions about MonteCarlo simulation in ADE Reply #6 - Jul 21^st, 2009, 8:33am Andrew Beckett wrote on Jul 21^st, 2009, 6:12am: Sounds very odd. What subversion of the IC tools are you using? Type: getVersion(t) in the CIW, and let me know what it says. Regards, Andrew. it is 5.10.41.500.6.131
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Andrew Beckett Senior Fellow Offline Life, don't talk to me about Life... Posts: 1742 Bracknell, UK	Re: Questions about MonteCarlo simulation in ADE Reply #7 - Jul 22^nd, 2009, 3:10am That's fairly recent. I'm not aware of any such issues, so I suggest you contact Cadence Customer support, with a testcase to illustrate the problem. Best Regards, Andrew.
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