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schehrazi

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Posts: 45
University of CA, LA

Saving simulation results in Cadence Spectre
May 21^st, 2006, 8:49am

Hi,

Assume you have run a long transient simulation and you want to save the voltage of a node vs. time so that you can take it to Matlab for some processing. I used some Ocean commands to do this, however, it turned out that for large number of points (>10000), it takes for ever for it to save the data. In fact, I waited for an hour and then stopped it because I had to do other things. It works fine for small number of data points though. I have no idea why this problem should exist but I want to make sure I am not doing anything wrong. Here are the commands which I used:

selectResults('tran)
x=v("out")
ocnPrint(?output "filename.txt" ?numberNotation 'scientific x)

Is there a better way to do this?

Thank you,

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Andrew Beckett

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Posts: 1742
Bracknell, UK

Re: Saving simulation results in Cadence Spectre
Reply #1 - Jul 20^th, 2006, 2:02pm

Well, for a start, MMSIM61 has a new "spectre toolbox" for matlab. This provides matlab commands so you can directly read spectre/spectreRF results directly into matlab (it's in <instdir>/tools/spectre/matlab , from memory).

Also, I think if you omit the numberNotation in your ocnPrint, it will be quicker. (again, this is from memory - I haven't checked).

Andrew.

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jbdavid Community Fellow Offline Posts: 378 Silicon Valley	Re: Saving simulation results in Cadence Spectre Reply #2 - Sep 2^nd, 2006, 12:14am ocnPrint (as Jay and I just discovered tonight) tries to read all the data into one list before printing it.. and so is limited to about 8K points.. 6.1 hasn't had the first QSR yet.. and I'd need to get new keys to use it.. but I will tell jay about it..
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Andrew Beckett Senior Fellow Offline Life, don't talk to me about Life... Posts: 1742 Bracknell, UK	Re: Saving simulation results in Cadence Spectre Reply #3 - Sep 20^th, 2006, 3:09am Jonathan, ocnPrint only has the 8K points limit if you do formatting on it - I think without that it's unlimited... Andrew.
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jbdavid Community Fellow Offline Posts: 378 Silicon Valley	Re: Saving simulation results in Cadence Spectre Reply #4 - Sep 30^th, 2006, 1:19am if I don't want formatting why would I want to use ocnPrint?
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Andrew Beckett

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Life, don't talk to
me about Life...

Posts: 1742
Bracknell, UK

Re: Saving simulation results in Cadence Spectre
Reply #5 - Dec 13^th, 2006, 8:56am

Hi Jonathan,

Well, if you want to get the numbers out, but you don't want them in suffix notation, or some other notation, you
can just use ?numberNotation "none" and it is much quicker. It even tells you this if you try doing it. i.e. if you
just want the raw numbers, without interpolation, without additional formatting, it is quick, and doesn't
have any point limits.

Andrew.

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