Improve Tecplot support

[mwestphal (Mathieu Westphal (Kitware))]

From a user voice request

The Tecplot reader is very usefull, but it should be further improved because many Tecplot files (written by the user according to Tecplot format specifications or written by Tecplot itself !) still cannot be read !

I am usually using Structured grid, and the Tecplot reader works fine for most of my ASCII files, except for those that are written by Tecplot itself and that contain the STRANDID and SOLUTIONTIME tokens that are currently unsupported. I have to remove these unsupported tokens from all ZONE headers before reading with Paraview. May I suggest to ignore those unsupported tokens with just a warning rather than stopping reading ?

Another problem is with Unstructured grids. I tried to read several ASCII Tecplot files with unstructured grids. Some of my files made Paraview freeze, other could not be read and gave many error messages such as :

“The record type XXX found in the file is unknown”

where xxx may be some coordinate data or something else.

It seems that the reader is bad positioned in the file because one or more token in the “ZONE” header are not recognized.

Looking at the reader source file, I tried to modify the header of simple Tecplot files with TRIANGLE or QUADRILATERAL elements, but I never succeeded in identifying which token is not recognized.

As most of complex CFD meshes have now unstructured grids, an improvement of the Tecplot reader for this type of grids would be greatly appreciated.

related:

Error reading in tecplot dat file

Hi, apologies if this has been asked before - i searched but couldn’t find an answer. I’m attempting to read in a .dat file with the Tecplot reader but keep encountering errors. The SOLUTIONTIME and STRANDID warnings can be solved by removing them from the header, but it doesn’t fix the record type error. That “record” is the first value in the dat file. If I read in as a Tecplot table the importer picks it up fine. Am I missing a simple formatting issue? Unlikely to be the issue, but this dat …

[todoooo (Todd)]

Impossible to solve without a data file.

[mwestphal (Mathieu Westphal (Kitware))]

It looks like many user have reported this, I hope someone will provide data at some point.

[pcrepier]

Maybe a suggestion that could be helpful.

Tecplot proposes their own library to write and read tecpot formatted files.
see here: The TecIO Library is available for download.

Maybe it is something worth considering instead of reverse engineering the format based on user-input ?

[todoooo (Todd)]

This requires that the user has purchased a licensed copy of TecPlot in order to have the dynamic libraries installed on their system.

[ldv]

I stumble on the same issue. Here are reduced snippets:

1/ The following works (data is node-based):

TITLE="FE_NODE_BASED"
VARIABLES = "X", "Y","P"
ZONE N=6, E=2, datapacking=block, zonetype= FEQUADRILATERAL
0,1,2,2,1,0
0,0,0,1,1,1
1,2,3,4,5,6
1,2,5,6
2,3,4,5

2/ The following is equivalent, but Paraview hangs (cpu at 100%):

TITLE="FE_NODE_BASED"
VARIABLES = "X", "Y","P"
ZONE N=6, E=2, datapacking=block, zonetype= FEQUADRILATERAL,varlocation=([1,2,3]=nodal)
0,1,2,2,1,0
0,0,0,1,1,1
1,2,3,4,5,6
1,2,5,6
2,3,4,5

3/ The following returns an error message (the variable P is face-based):

TITLE="FE_CELL_CENTERED"
VARIABLES = "X", "Y","P"
ZONE N=6, E=2, datapacking=block, zonetype= FEQUADRILATERAL,varlocation=([1,2]=nodal,[3]=cellcentered)
0,1,2,2,1,0
0,0,0,1,1,1
1,2
1,2,5,6
2,3,4,5

Message:

ERROR: In …/VTK/IO/Geometry/vtkTecplotReader.cxx, line 2179

vtkTecplotReader (0x55e5d577b6b0): /home/ted/test/h.dat: The record type 1 found in the file is unknown.

It would be great if Paraview could read in those valid TECPLOT files.

Tested with Paraview 5.9.0