Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Max value of a field and its coordinates

Please login with a confirmed email address before reporting spam

Hello,

I know that there have been a lot of posts about this topic and I have read many of them but I am still as dumb as before.

I need to find the value of the maximum value of the field in a domain and its r and z coordinates.
I defined a maxop1 operator in model definitions. I then go to the results/derived values and find the value of maxop1(mf.Br,r). It gives me a value which I think is the value of the r-coordinate. However it does not say anything about its value which is what I primarily am interested in.

So i still cannot find out how to calculate the masimum field as well as its r and z coordinates.

Please tell me in a way that I can understand how to do this.

Thanks for any help.
Kamil

5 Replies Last Post 05.02.2014, 05:31 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 20.11.2012, 01:26 GMT-5
Hi

check the doc, the max(myfield) give you the value max(myfield,x) the x coordinates etc, you need to call your max(9 operator 4 times in 3D to get the full info

--
Good luck
Ivar
Hi check the doc, the max(myfield) give you the value max(myfield,x) the x coordinates etc, you need to call your max(9 operator 4 times in 3D to get the full info -- Good luck Ivar

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 20.11.2012, 03:54 GMT-5
Thank you Ivar,
However I get errors.
I am trying to find the maximum value of the magnetic flux density (r-component) which is mf.Br.
I write max(mf.Br) to find out the maximum value but I get error message saying that the number of parameters does not match.
I try to find out the r-coordinate and type max(mf.Br,r) and get a value but this is the wrong value because I have exported all the field values and their coordinates via a report and can see all the values.
Where can I see the doc? I am using university license. Can it be so that I don't have access to the doc?
Thank you for your reply.
Kamil
Thank you Ivar, However I get errors. I am trying to find the maximum value of the magnetic flux density (r-component) which is mf.Br. I write max(mf.Br) to find out the maximum value but I get error message saying that the number of parameters does not match. I try to find out the r-coordinate and type max(mf.Br,r) and get a value but this is the wrong value because I have exported all the field values and their coordinates via a report and can see all the values. Where can I see the doc? I am using university license. Can it be so that I don't have access to the doc? Thank you for your reply. Kamil

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 20.11.2012, 07:45 GMT-5
Hi

I do not believe there is any difference betzween uni or industrial licence, on the functionality of the software.

But certainly it could be the version 4.0 was an early/first major release version not really ironed out


--
Good luck
Ivar
Hi I do not believe there is any difference betzween uni or industrial licence, on the functionality of the software. But certainly it could be the version 4.0 was an early/first major release version not really ironed out -- Good luck Ivar

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 03.02.2014, 09:16 GMT-5
I have exactly the same problem.

I have a 1D Plot - Line Graph and I want to plot the "normalized" data, I mean, I want to plot:
mf.Bz/max(mf.Bz), so that the maximum is 1. But this doesn't work: 'max' function requires 2 inputs.

Any suggestion?
I have exactly the same problem. I have a 1D Plot - Line Graph and I want to plot the "normalized" data, I mean, I want to plot: mf.Bz/max(mf.Bz), so that the maximum is 1. But this doesn't work: 'max' function requires 2 inputs. Any suggestion?

Magnus Ringh COMSOL Employee

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 05.02.2014, 05:31 GMT-5
Hi,

You can use a Maximum coupling operator, which you add from the Definitions node under the Component node. In its settings window, define its source as the same boundaries that you plot mf.Bz along. Notice the name of the maximum operator; by default it is maxop1. After re-solving or updating the solution, you can then plot mf.Bz/maxop1(mf.Bz), which will be "normalized" so that all values are between -1 and 1.

Best regards,
Magnus Ringh, COMSOL
Hi, You can use a Maximum coupling operator, which you add from the Definitions node under the Component node. In its settings window, define its source as the same boundaries that you plot mf.Bz along. Notice the name of the maximum operator; by default it is maxop1. After re-solving or updating the solution, you can then plot mf.Bz/maxop1(mf.Bz), which will be "normalized" so that all values are between -1 and 1. Best regards, Magnus Ringh, COMSOL

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.