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Exporting data while solving

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Hi,

I am relatively new to COMSOL. Is there anyway to write the data generated up to a point while solving into an external file like excel or .txt which can be opened in COMSOL at a later point of time?
I have come across discussions to export data while solving in case of a parametric sweep, but nothing to go on in terms of writing data generated as it is being solved.
This way, instead of letting the data go as a waste, at least a partial solution can be retained.

Thank you.

5 Replies Last Post 23 ago 2016, 22:38 GMT-4

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Posted: 8 years ago 29 apr 2016, 17:14 GMT-4
You can define a domain probe point in definitions node which is evaluated a chosen variable in table while solving. The variable at the chosen point is evaluated in table and plotted in a graph as function of time.
You can define a domain probe point in definitions node which is evaluated a chosen variable in table while solving. The variable at the chosen point is evaluated in table and plotted in a graph as function of time.

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Posted: 8 years ago 29 apr 2016, 18:07 GMT-4

You can define a domain probe point in definitions node which is evaluated a chosen variable in table while solving. The variable at the chosen point is evaluated in table and plotted in a graph as function of time.


Thank you very much.
So, this would essentially plot the variable we need while the solver is still working in addition to the default convergence plots of the segregated groups.
Is there any way to write this data to an external file outside COMSOL like excel or txt to local disk while the solver is running at regular intervals so that it can be accessed even if it crashes or becomes unresponsive? Basically like creating a back up recovery disc to your windows data so that you won't loose it if your system runs into trouble.

- Jathin
[QUOTE] You can define a domain probe point in definitions node which is evaluated a chosen variable in table while solving. The variable at the chosen point is evaluated in table and plotted in a graph as function of time. [/QUOTE] Thank you very much. So, this would essentially plot the variable we need while the solver is still working in addition to the default convergence plots of the segregated groups. Is there any way to write this data to an external file outside COMSOL like excel or txt to local disk while the solver is running at regular intervals so that it can be accessed even if it crashes or becomes unresponsive? Basically like creating a back up recovery disc to your windows data so that you won't loose it if your system runs into trouble. - Jathin

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Posted: 8 years ago 29 apr 2016, 18:27 GMT-4
For some old versions it is possible when you run simulation via script on Linux.

--
Pu, ZHANG
DTU Fotonik
For some old versions it is possible when you run simulation via script on Linux. -- Pu, ZHANG DTU Fotonik

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Posted: 8 years ago 30 mag 2016, 19:16 GMT-4
Hello Jathin,

in the 5.x versions of COMSOL it is possible to choose the place to store a table within the model or in an external file or both. Is this option already there in 4.4?

If so, by choosing to store the probe table table in an external file, you can get the results with an external program even while COMSOL is still solving.

Regards
Andre
Hello Jathin, in the 5.x versions of COMSOL it is possible to choose the place to store a table within the model or in an external file or both. Is this option already there in 4.4? If so, by choosing to store the probe table table in an external file, you can get the results with an external program even while COMSOL is still solving. Regards Andre

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Posted: 8 years ago 23 ago 2016, 22:38 GMT-4
Hello,

I export the table data out while it is running and choose the storage on file. But I got a very large txt file with more than 2G. Something is wrong as the probe table is just few kb.

Do you have any idea where is wrong? By the way I am using version 5.2

thanks and regards,
Hansong
Hello, I export the table data out while it is running and choose the storage on file. But I got a very large txt file with more than 2G. Something is wrong as the probe table is just few kb. Do you have any idea where is wrong? By the way I am using version 5.2 thanks and regards, Hansong

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