# Parallel VTKHDF

**URL:** https://discourse.paraview.org/t/parallel-vtkhdf/17182
**Category:** ParaView Support
**Created:** [September 11, 2025, 5:02am UTC](https://discourse.paraview.org/t/parallel-vtkhdf/17182 "2025-09-11T05:02:15Z")
**Posts on this page:** 5
**Page:** 1

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### Author: ![Frankx9](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/f/3e96dc/32.png) [@Frankx9](https://discourse.paraview.org/u/Frankx9)
#### Post date: [September 11, 2025, 5:02am UTC](https://discourse.paraview.org/t/parallel-vtkhdf/17182/1 "2025-09-11T05:02:15Z")

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Hi,

could you point me out to where do I find a file example of the parallel VTKHDF (the equivalent of .pvtu) that is in Paraview that I can potentially download and inspect?  
Any further documentation that I might look at while trying to implement it?

Best

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### Author: ![Lucas\_Givord](https://discourse.paraview.org/user_avatar/discourse.paraview.org/lucas_givord/32/6851_2.png) [@Lucas\_Givord](https://discourse.paraview.org/u/Lucas_Givord)
#### Post date: [September 11, 2025, 7:13am UTC](https://discourse.paraview.org/t/parallel-vtkhdf/17182/2 "2025-09-11T07:13:05Z")

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Hi @Frankx9,

You can check the can-pvtu.hdf dataset from VTK Testing data folder, you can also retrieve it from here : [https://vtk.org/files/ExternalData/SHA512/6a8f72693e881bd9044c107e347bf2501f1e43719d32733c9dfca2a48fdcb45c2a85d3d3a6f86adbc6f9a4d494be83b73b8a44b312996459647108ba222b14fa](https://vtk.org/files/ExternalData/SHA512/6a8f72693e881bd9044c107e347bf2501f1e43719d32733c9dfca2a48fdcb45c2a85d3d3a6f86adbc6f9a4d494be83b73b8a44b312996459647108ba222b14fa)

All information (spec, example and so on) is here: [VTKHDF File Format - VTK documentation](https://docs.vtk.org/en/latest/vtk_file_formats/vtkhdf_file_format/index.html)

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### Author: ![Frankx9](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/f/3e96dc/32.png) [@Frankx9](https://discourse.paraview.org/u/Frankx9)
#### Post date: [September 11, 2025, 8:21am UTC](https://discourse.paraview.org/t/parallel-vtkhdf/17182/3 "2025-09-11T08:21:20Z")

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Hi Lucas,

thanks a lot!  
I already checked the documentation but for I didn’t understand where does the difference lay in the parallel one w.r.t to the standard VTKHDF. Do you have any additional insight?

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### Author: ![Lucas\_Givord](https://discourse.paraview.org/user_avatar/discourse.paraview.org/lucas_givord/32/6851_2.png) [@Lucas\_Givord](https://discourse.paraview.org/u/Lucas_Givord)
#### Post date: [September 11, 2025, 8:39am UTC](https://discourse.paraview.org/t/parallel-vtkhdf/17182/4 "2025-09-11T08:39:57Z")

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Everything when we talk about “partition” is for the parallel support : [VTKHDF format specification - VTK documentation](https://docs.vtk.org/en/latest/vtk_file_formats/vtkhdf_file_format/vtkhdf_specifications.html#unstructured-grid)

Some dataset will be of size N where N is the number of partition, like `NumberOfCells` …  
If we take as example the can-pvtu.hdf dataset :

 ![image](https://discourse.paraview.org/uploads/default/original/3X/e/d/edd07db1249563804a84c1a788a106df8b6c30f7.png)

`NumberOfCells` size is equal to 3, meaning that this dataset is partitioned in 3 parts, first part has 2541 cells etc…

Then some other datasets will reuse these information:

 ![image](https://discourse.paraview.org/uploads/default/original/3X/4/5/45a34f5366720340ab0abc652b6f9fefae38dd71.png)

like `CellData`, which will read for the first part only the 2541 first values and so on.

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<div class="post-metadata">

### Author: ![Frankx9](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/f/3e96dc/32.png) [@Frankx9](https://discourse.paraview.org/u/Frankx9)
#### Post date: [September 12, 2025, 8:47am UTC](https://discourse.paraview.org/t/parallel-vtkhdf/17182/5 "2025-09-12T08:47:17Z")

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Thanks a lot Lucas! Really grateful for the help