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Maxima of multiple time series
Posted 22 gen 2016, 09:55 GMT-5 Parameters, Variables, & Functions, Results & Visualization Version 5.2 3 Replies
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what is the easiest way of extracting the maximum value from two times series which are normalized volume and surface integrals? Perhaps I am being stupid, but there doesn't seem to be a natural way of doing this in the comsol gui.
Another way of asking the question is how can i extract and compare data from two tables produced from derived values.
Another way of asking the question is how can i extract and compare data from two tables produced from derived values.
3 Replies Last Post 19 feb 2016, 08:51 GMT-5
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Posted:
10 years ago
Dear David,
Thank you for your post.
Whenever you have a time series data and are evaluating an expression in the Derived Values node, there is setting regarding the Data Series Operation. The default "None" returns the expression at all time steps. The operation "Maximum" will return the maximum value over the time series data.
I hope this answers your query, however if it has been misunderstood, please feel to open a new support case via our dedicated Technical Support Portal: uk.comsol.com/support which you are entitled to use through your existing subscribed license.
Kind regards,
Andrew
COMSOL Technical Support
Thank you for your post.
Whenever you have a time series data and are evaluating an expression in the Derived Values node, there is setting regarding the Data Series Operation. The default "None" returns the expression at all time steps. The operation "Maximum" will return the maximum value over the time series data.
I hope this answers your query, however if it has been misunderstood, please feel to open a new support case via our dedicated Technical Support Portal: uk.comsol.com/support which you are entitled to use through your existing subscribed license.
Kind regards,
Andrew
COMSOL Technical Support
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Posted:
10 years ago
thanks Andrew. This is okay, but if you run a parametric sweep then you only get the maximum of all the data - just a single value - rather than a maximum per parameter. it is not very robust.
instead I used the global evaluation to define the maximum of a field, T, as Tmax, where
Tmax - max( maxop1(T), prev(Tmax,1) ) = 0
using a time discrete solver. This returns the maximum value. I can then plot the last value of Tmax against the parameter varied in the parametric sweep.
this is a bit of a hack; adds another variable to be computed; and forces the use of the discrete time solver. Is there an easier or another way?
instead I used the global evaluation to define the maximum of a field, T, as Tmax, where
Tmax - max( maxop1(T), prev(Tmax,1) ) = 0
using a time discrete solver. This returns the maximum value. I can then plot the last value of Tmax against the parameter varied in the parametric sweep.
this is a bit of a hack; adds another variable to be computed; and forces the use of the discrete time solver. Is there an easier or another way?
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Posted:
10 years ago
Have you considered creating a quick app for that?
Any time I want to perform the same post-processing operation repeatedly, a method with a for loop is my first thought. This has popped up a few times in the Discussion Forum recently, see www.comsol.com/community/forums/general/thread/90731 , www.comsol.com/community/forums/general/thread/100121 , www.comsol.com/community/forums/general/thread/94851 .
Jeff
Any time I want to perform the same post-processing operation repeatedly, a method with a for loop is my first thought. This has popped up a few times in the Discussion Forum recently, see www.comsol.com/community/forums/general/thread/90731 , www.comsol.com/community/forums/general/thread/100121 , www.comsol.com/community/forums/general/thread/94851 .
Jeff