Hello Ishan,

Reconstructing a parallel solution does not need to be done in parallel. Perhaps with some very large solution files this is necessary, but in my experience, reconstructing in serial can be quite efficient too.

Because you say your solution is decomposed, case_0.chk must be a directory. What I have done in the past is: FieldConvert case.xml case_0.chk/ case_0.vtu
The only differences between this and the command you were using are that I'm running in serial and I added a "/" to the end of the case_0.chk. You could try this with mpirun -np 10 in front as well. Just make sure you have the "/". If you are using FieldConvert with a different number of processors than you ran the simulation with, this may not work but give it a try. If you still can't get it to work, please send your error message.

I would also recommend using the HDF5 output option which will tell your simulation to output solution files that are already reconstructed. You will still have to convert the files to a format readable by Paraview but it's helpful to have fewer files in case you need to save many time steps and your cluster has a file count limit. There are several other benefits of HDF5 with Nektar++.

Please let me know if this helps and if you have more questions.

All the best,
Isaac
From: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> on behalf of Nande, Ishan A. <ian9@leicester.ac.uk>
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To: nektar-users@imperial.ac.uk <nektar-users@imperial.ac.uk>
Subject: [Nektar-users] Using FieldConvert for parallel solution files
 
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Hello,

 

I hope everyone is ok.

 

I am a new user of Nektar++ and in a bind. Specifically, I am stuck on using the FieldConvert utility to re-construct the decomposed solution files generated when the AcousticSolver was run with mpirun.I have referred to the user guide Section 5.7(Version 5.3.0) but it doesn’t work.

 

I tried to run the FieldConvert with 10 processors like this: mpirun -np 10 FieldConvert case.xml case_0.chk case_0.vtu. This didn’t work and throws errors. This syntax matches with what is mentioned in Section 5.7 of the user guide.

 

What would be the right way to using FieldConvert when you have solution files that have been generated in parallel run ?

 

Regards,

Ishan

PGR