Re: [deal.II] Error estimation using a function of your solution vector

2019-07-03 Thread Daniel Arndt
Bruno

Hello everyone,
> I was wondering what was the simplest way to carry out error estimation
> using a function of your solution vector. For example, to carry out mesh
> adaptation using  a Kelly Error estimator but using the vorticity as the
> input variable instead of the velocity vector.
> Is there a way to do it in a similar fashion as the way we can
> post-process with DataPostprocessorScalar or
> DataPostprocessorVector? (which is what we use for the vorticity and
> the q-criterion post-processing)
>
DataPostprocessor computes values in certain evaluation points that are not
(necessarily) related to any given finite element space.
On the other hand, KellyerrorEstimator expects a finite element vector.
What you need to do is to represent the vorticity in some finite element
space.
You would typically either interpolate or project with respect to this new
space.

Best,
Daniel

-- 
The deal.II project is located at http://www.dealii.org/
For mailing list/forum options, see 
https://groups.google.com/d/forum/dealii?hl=en
--- 
You received this message because you are subscribed to the Google Groups 
"deal.II User Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to dealii+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/dealii/CAOYDWb%2BrTm-c_KA09m%3Dt0CCRHagavw-41YmibkL7OOPTEPsrLA%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.


[deal.II] Error estimation using a function of your solution vector

2019-07-03 Thread Bruno Blais
Hello everyone, 
I was wondering what was the simplest way to carry out error estimation 
using a function of your solution vector. For example, to carry out mesh 
adaptation using  a Kelly Error estimator but using the vorticity as the 
input variable instead of the velocity vector.
Is there a way to do it in a similar fashion as the way we can post-process 
with DataPostprocessorScalar or DataPostprocessorVector? (which 
is what we use for the vorticity and the q-criterion post-processing)

I have tried looking through the documentation of the Kelly error estimator 
or the steps, but I have not found a similar example.

If such postprocessor cannot be used, what would you suggest to be the best 
way?
I am afraid my knowledge on error estimator is really limited.
Best regards and thank you for your time.
Bruno

-- 
The deal.II project is located at http://www.dealii.org/
For mailing list/forum options, see 
https://groups.google.com/d/forum/dealii?hl=en
--- 
You received this message because you are subscribed to the Google Groups 
"deal.II User Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to dealii+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/dealii/495a6a9b-1767-4977-bffc-0c8a7a350870%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.