Cannot create streamlines from groundwater heads .vtu-file

Hi everyone,

I am having trouble to create stream lines from a vtu file which contains groundwater head values. It displays fine but the stream tracer filter is disabled. I researched online and found that it might be necessary to create the vectors first. To do that I tried to use the programmable filter (as advised here) but it gives me the error that U and V are unknown. When I look at the information tab at the file I noticed, that there are no data arrays and the dimensions (number of cells and points) are set to zero. This surprises me because the vtu is clearly displayed with the correct values. I have little experience working on vtu files, so I don’t know
what’s wrong with it. I also have a .pvd file created with the same code, however Paraview throws an error when I load it:

ERROR: In C:\glr\builds\paraview\paraview-ci\build\superbuild\paraview\src\VTKExtensions\IOCore\vtkXMLCollectionReader.cxx, line 444
vtkPVDReader (000001E4BA15BC90): Could not determine the data type for the first dataset. Please make sure this file format is supported.

ERROR: In C:\glr\builds\paraview\paraview-ci\build\superbuild\paraview\src\VTK\Common\ExecutionModel\vtkExecutive.cxx, line 753
vtkPVCompositeDataPipeline (000001E4B3873960): Algorithm vtkPVDReader(000001E4BA15BC90) returned failure for request: vtkInformation (000001E4AB30CB00)
  Debug: Off
  Modified Time: 2596371
  Reference Count: 1
  Registered Events: (none)

So maybe the file is damaged? If needed I can provide the data via google drive or so…


please share the files

should be available here

Here is your corrected .pvd file.

spandau-flopy_head.pvd (287 Bytes)

The filename was not complete

Thanks a lot!!
However, how do I solve the original issue now? I assumed that the files might be somehow connected - which I guess is not the case. Is it actually possible to apply the stream tracer filter on the .vtu file or am I making a mistake here?

When I follow these instructions on either of the two files I get the error message below. It seems to be related to the names of the vector. How do I find out which name would be the correct one for my file?

Traceback (most recent call last):
  File "C:\Program Files\ParaView 5.9.0-RC2-Windows-Python3.8-msvc2017-64bit\bin\Lib\site-packages\paraview\detail\", line 203, in execute
    retVal = compute(inputs, expression, ns=variables)
  File "C:\Program Files\ParaView 5.9.0-RC2-Windows-Python3.8-msvc2017-64bit\bin\Lib\site-packages\paraview\detail\", line 146, in compute
    retVal = eval(subEx, globals(), mylocals)
  File "<string>", line 1, in <module>
NameError: name 'U' is not defined

Your data does not contain any point based vectors, so you can’t apply a stream tracer on it.