Max value of a transient parameter

ahmadsohrabi69 · May 15, 2016, 11:47

Hi,
I'm trying to optimize a specific parameter obtained from CFX, using genetic algorithm.
when I run a transient problem I can only check the result for different time steps using time step selector manually.
How can I write an Expression to obtain the max value of a parameter between all transient results at a location automatically?

I need this Expression for the input of my genetic algorithm

thank you.

-Maxim- · May 17, 2016, 03:35

one idea: write an expression ( maxValue(variable)@location) and use this expression as a monitor. You can easily export those values via right-click from the solver manager's monitor or with a script cfx5mondata.
If you don't know how do create those things, please have a look at the documentation or use the search function in this forum

In case you already have a lot of *.trn files - you could write a script that loops through all those files and gets the values. But since I haven't done that before, I'm not sure exactly how that works.

ahmadsohrabi69 · May 17, 2016, 13:52

Quote:

Originally Posted by -Maxim-

one idea: write an expression ( maxValue(variable)@location) and use this expression as a monitor. You can easily export those values via right-click from the solver manager's monitor or with a script cfx5mondata.
If you don't know how do create those things, please have a look at the documentation or use the search function in this forum

In case you already have a lot of *.trn files - you could write a script that loops through all those files and gets the values. But since I haven't done that before, I'm not sure exactly how that works.

Thanks a lot Maxim. my problem exactly is how to write a script to loop through my results automatically and give the maximum value automatically to genetic algorithm. I don't want to save the plot manually and check the maximum value myself.

-Maxim- · May 18, 2016, 03:05

have you searched this forum for scripting ideas? In case you didn't set up any monitor points, you'll have to loop through all your trn files.

those are the first 3 search results:
http://www.cfd-online.com/Forums/cfx...-file-csv.html
http://www.cfd-online.com/Forums/cfx...lem-macro.html
http://www.cfd-online.com/Forums/cfx...ding-halt.html

As soon as you have written some code, the guys here can probably help debugging in case you will still have problems. good luck

May 15, 2016, 11:47	Max value of a transient parameter	#1
ahmadsohrabi69 New Member Ahmad Join Date: Nov 2015 Posts: 2 Rep Power: 0	Hi, I'm trying to optimize a specific parameter obtained from CFX, using genetic algorithm. when I run a transient problem I can only check the result for different time steps using time step selector manually. How can I write an Expression to obtain the max value of a parameter between all transient results at a location automatically? I need this Expression for the input of my genetic algorithm thank you.

May 17, 2016, 03:35		#2
-Maxim- Senior Member Maxim Join Date: Aug 2015 Location: Germany Posts: 413 Rep Power: 13	one idea: write an expression ( maxValue(variable)@location) and use this expression as a monitor. You can easily export those values via right-click from the solver manager's monitor or with a script cfx5mondata. If you don't know how do create those things, please have a look at the documentation or use the search function in this forum In case you already have a lot of *.trn files - you could write a script that loops through all those files and gets the values. But since I haven't done that before, I'm not sure exactly how that works. ahmadsohrabi69 likes this.

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May 18, 2016, 03:05		#4
-Maxim- Senior Member Maxim Join Date: Aug 2015 Location: Germany Posts: 413 Rep Power: 13	have you searched this forum for scripting ideas? In case you didn't set up any monitor points, you'll have to loop through all your trn files. those are the first 3 search results: http://www.cfd-online.com/Forums/cfx...-file-csv.html http://www.cfd-online.com/Forums/cfx...lem-macro.html http://www.cfd-online.com/Forums/cfx...ding-halt.html As soon as you have written some code, the guys here can probably help debugging in case you will still have problems. good luck