Does paraview still work with CGNS files?

Hi all, I am a student working on computational fluid dynamics, and I do simulations which generates cgns files. I used to use paraview 4.2 to process the data and generate figures/videos, recently we updated our CGNS and HDF5 to a newer version, and paraview 4.2 stopped working with my input. And I found that newer versions of paraview doesn’t naturally support CGNS/HDF5 files.

Is there any sort of plugins which I can install in order to be able to process CGNS files with paraview?

Many Thanks!

Have you tried ParaView 5.5.2? Also, try a nightly build? There has been a lot of work in ParaView with CGNS over the last year or so.

If this doesn’t fix the issue, mind posting a dataset, and directions how to replicate the issue?


Hi, Thanks for your reply.

I tried using 5.5.2(I downloaded the binary, didn’t build from source code), the problem is like before, Paraview will give me a message saying that a reader for my file can’t be found and ask me to manually select a reader from a provided list where there is no CGNS reader.

My cgns files are built with parallel cgns version 3.3.1 and parallel hdf5 1.10.1, I can read and process them with python h5py module after it’s properly built from my local hdf5 library. Do I have to build paraview from source as well?


Could you post a file that shows this issue?



I shared some of those files on google drive:


Current ParaView (5.5.2) does not recognize these files. Please download ParaView 5.6.0-rc2, from the ParaView website. This works correctly.

You gave me three files. Files flow-10.00.cgns opens correctly. grid.cgns opens correctly. part-10.00.cgns crashes. Could you try opening this dataset with cgnsview, and make sure your dataset isn’t bad?

Hi all,

I am experiencing a very similar issue using ParaView 5.8.0 on Windows. Everything works fine when reading small/medium size grids, but when I try to visualize large CGNS meshes (50M to 150M elements), ParaView can’t find an appropriate reader.

The official cgns checker passes, and I can visualize my grid using cgns view/plot.

Another interesting thing I noticed: On my Linux laptop (using ParaView 5.8.0), ParaView actually recognizes the CGNS format, but crashes later on because I don’t have enough RAM. However, a colleague tried to open a similar grid on Linux using ParaView 5.2 and faced the unrecognized reader issue. I will try installing a more recent version of ParaView on a Linux workstation to see if the issue was fixed in Linux between 5.2 and 5.8.

Is there something I am missing? What could I do to visualize my CGNS mesh in ParaView?

I’m using Paraview 5.10.1 and it isn’t offering any fields in a simple file (generated by the CGNS user manual examples). This file has “Density” and “Pressure” fields when opened in VisIt, but no such fields in Paraview.

grid_c.cgns (245.6 KB)

Make sure you check arrays listed under Point Arrays. With the grid_c.cgns file you attached, this is what I see. Density and Pressure are indeed available, just not read by default. You need to enable them in the reader’s Properties.

Oh, how embarrassing. Thanks, that’s working.

Is it expected to work with higher order elements (cubic 0036 and quartic 0038 CFD General Notation System)? I get this with the cubic elements produced by src/tests/elemtest.c, but cgnscheck elemtest.cgns has warnings too so I don’t know if it’s a fair test. I’d be happy if reading HEXA_64 is expected to work (reducing to linear internally is fine).

(   6.500s) [paraview        ]      vtkCGNSReader.cxx:2447   ERR| vtkCGNSReader (0x55821eb691b0): Mixed definition of unstructured zone by elements and by faces is not valid.
(   6.503s) [paraview        ]      vtkCGNSReader.cxx:4608   ERR| vtkCGNSReader (0x55821eb691b0): Error Reading file
(   6.503s) [paraview        ]       vtkExecutive.cxx:752    ERR| vtkPVCompositeDataPipeline (0x55821c2922c0): Algorithm vtkCGNSFileSeriesReader(0x7f4d340087e0) returned failure for request: vtkInformation (0x55821dda85d0)
  Debug: Off
  Modified Time: 407151
  Reference Count: 1
  Registered Events: (none)

elemtest.cgns (118.5 KB)