How to use mesh write --> SU2 ?

[antares190]

Dear all,
I'm trying to test the read / write capabilities of meshio, particularly when it comes to SU2 file format. To test it I downloaded an *.su2 mesh file from the github tutorial repository (here), and was trying to simply have a "read SU2 ---> write SU2 to a different name" python script

Absolutely nothing fancy:

import meshio
import numpy as np
from scipy.spatial import cKDTree
from collections import defaultdict
import json


def readWriteSU2(original_su2, output_su2):
    original = meshio.read(original_su2)

    meshio.write(output_su2, original, file_format="su2")
    




if __name__ == "__main__":
    import argparse

    parser = argparse.ArgumentParser(description="Read SU2 write SU2")
    parser.add_argument("original_su2", help="Original SU2 mesh with markers")
    parser.add_argument("output_su2", help="Output reconstructed .su2 mesh")

    args = parser.parse_args()

    readWriteSU2(args.original_su2, args.output_su2)

When I run it, it goes through the read part without errors (but with some warnings) :

Warning: meshio does not support tags of string type.
    Surface tag  FARFIELD will be replaced by 1
Warning: meshio does not support tags of string type.
    Surface tag  SYMMETRY will be replaced by 2
Warning: meshio does not support tags of string type.
    Surface tag  WING will be replaced by 3
Warning: meshio could not parse line
 0.000000000000000e+00  0.000000000000000e+00   0.000000000000000e+00
 skipping.....
Warning: meshio could not parse line
 0.000000000000000e+00  0.000000000000000e+00   0.000000000000000e+00
 skipping.....
Warning: meshio could not parse line
 0.000000000000000e+00  0.000000000000000e+00   0.000000000000000e+00
 skipping.....

But crashes in the write part:

Exception has occurred: TypeError
cannot unpack non-iterable CellBlock object
  File "/data/SIMS/TEST/CFD/SU2/meshIOTest/pymeshioSU2toSU2_test.py", line 14, in readWriteSU2
    meshio.write(output_su2, original, file_format="su2")
  File "/data/SIMS/TEST/CFD/SU2/meshIOTest/pymeshioSU2toSU2_test.py", line 29, in <module>
    readWriteSU2(args.original_su2, args.output_su2)
TypeError: cannot unpack non-iterable CellBlock object

Now, what am I doing wrong? Is there a working workaround?

Thanks all

[antares190]

I modified slightly the _su2.py source, and it now works as expected.

Original
341 for index, (cell_type, data) in enumerate(mesh.cells):

Modified :

            #for index, (cell_type, data) in enumerate(mesh.cells):# original
            for index, cell_block in enumerate(mesh.cells):
                cell_type = cell_block.type
                data = cell_block.data
                # Now you can work with cell_type, data, and index