pvtu (unstructured)

[AliE89]

Ciao Stefano,

Do you have an example to write pvtu?

I can only find pvts in the examples and the source file seems to include pvts only.

Thanks!

[AliE89]

Ok, sorry I have misunderstood the usage. It works for pvtu. Here what I have done, it can be usefull to other users as well:

		ierr = pvtk_field_file%initialize(filename='postProc/VTKfields/Parallel/mesh.pvtu', &
				                          mesh_topology='PUnstructuredGrid', mesh_kind="Float64")

		ierr = pvtk_field_file%xml_writer%write_dataarray(location='cell', action='open')

		!error = pvtk_field_file%xml_writer%write_parallel_dataarray(data_name='int32_scalar', &
		!		data_type='Int32', &
		!		number_of_components=1)

		ierr = pvtk_field_file%xml_writer%write_dataarray(location='cell', action='close')

		ierr = pvtk_field_file%xml_writer%write_parallel_geo(source="./file1.vtu")
		ierr = pvtk_field_file%xml_writer%write_parallel_geo(source="./file2.vtu")

		ierr = pvtk_field_file%finalize()

[szaghi]

@AliE89

I am sorry for my delay.

Have you solved it? I have to improve examples and docs, my bad.

[AliE89]

Hi Stefano, Yes it was really easy doing that, i found an example in the doc in the end :) I am still a bit puzzled on polyheadral cells, any suggestion?

…

On Fri, 12 Mar 2021, 09:07 Stefano Zaghi, ***@***.***> wrote: @AliE89 <https://github.com/AliE89> I am sorry for my delay. Have you solved it? I have to improve examples and docs, my bad. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#32 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AL4ZV6QK6MHQ4I37K2NNPVTTDHDU5ANCNFSM4UCLC6HQ> .

[szaghi]

@AliE89

I am still a bit puzzled on polyheadral cells, any suggestion?

Indeed, nope because I have never used poly output. I'll try to figure out how complicated is to support it (I guess not so complicated), but I cannot plan a timeline right now, I am really too much busy with my official work.

[lj-cug]

I also need a tutorial for writing pvtu format for my cfd code. But I cannot find any example code. Especially a complete example code for 3D prism data.
Thanks!
Li Jian

[AliE89]

Hi, Hope Stefano does not mind if I reply to your question. You cannot write a pvtu file directly, but pvtu is just a plain file where you basically link toghether N vtu files. So if your code is parallel , you let each partition write a vtu file with vtk fortran then your master node just writes down the pvtu. You can see an example at: https://gitlab.com/alie89/flubio-code-fvm/-/blob/main/src/pre_post_proc/parallelPost/formats/vtkFormat.f03?ref_type=heads I can provide you an example file tomorrow. Cheers Il Gio 19 Giu 2025, 15:48 lj-cug ***@***.***> ha scritto:

…

*lj-cug* left a comment (szaghi/VTKFortran#32) <#32 (comment)> I also need a tutorial for writing pvtu format for my cfd code. But I cannit find any example code. Thanks! Li Jian — Reply to this email directly, view it on GitHub <#32 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AL4ZV6XPAIPYKVEYR27U6733EK5TBAVCNFSM6AAAAAB7V7Q7GSVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDSOBYGE3TGNBYGY> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[lj-cug]

My CFD code outputs the results files and the local-to-global mapping information files at every rank. So I think the .pvtu file should contain the similar local-to-global mapping information.
In VTKFortran, the vtu files are stored for each partition, how about the ghost cells or nodes? I don't see this storage in pvts example codes.
Li Jian

[AliE89]

Personally I do not use any ghost level in my setup, I just need to link together the *.vtu file each partition is writing. Here an example on how to write a pvtu file: ?xml version="1.0"?> <VTKFile type="PUnstructuredGrid" version="1.0" byte_order="LittleEndian"> <PUnstructuredGrid GhostLevel="0"> <PPoints> <PDataArray type="Float64" NumberOfComponents="3" Name="Points"/> </PPoints> <PCellData> <PDataArray type="Float64" Name="Fx" NumberOfComponents="3"/> <PDataArray type="Float64" Name="rhoc" NumberOfComponents="1"/> </PCellData> <Piece Source="./flubioField-d0.vtu"/> <Piece Source="./flubioField-d1.vtu"/> <Piece Source="./flubioField-d2.vtu"/> <Piece Source="./flubioField-d3.vtu"/> </PUnstructuredGrid> </VTKFile> You can write your own function to write down this file. I am not sure ghost level is relevant for plain visualisations. Let me know your thoughts! Edoardo

[szaghi]

Hi @lj-cug I am sorry, but I am currently busy. I'll try to provide an example next week, but I cannot promise.

Thank you @AliE89 for your help, it is really appreciated 👍

@lj-cug, you can save ghost cells as well as the inner-domain cells. I do this often: simply pass the whole domain to the grid (topology and fields routine) instead of just the inner cells.

Stefano

[lj-cug]

@AliE89 Thank you for your FLUBIO example code, I will learn how to use VTKFortran output in my Fortran hydrodynamic code. It's helpful! Following your example code, I think I should output the local node and cell number for each partition in .vtu, and the "GhostLevel =0" in .pvtu. The ghost level will be overlapped between 2 partitions. And also someone asked the question in the forum of Paraview as in https://discourse.paraview.org/t/pvtu-example/15441
@szaghi More example codes are better, especially pvtu with ghost level information.