Is vtkUnstructuredGrid part of vtkDataSet

ParaView Support
#1

I have a clipped data set called vtk_data. It is a vtkUnstructuredGrid type

print(vtk_data.GetDataInformation(0).GetDataClassName())
>> vtkUnstructuredGrid

When I check if it is ‘vtkDataSet’ it returns 0

vtk_data.GetDataInformation(0).IsA("vtkDataSet")
>> 0
#2

This is because you’re not working directly with the dataset but the client’s representation of the dataset. I’d bet that if you do vtk_data.GetDataInformation(0).IsA("vtkUnstructuredGrid") that you’d get the same result since the class that you’re working on isn’t actually the dataset itself but the client’s representation of what is on the server.

#4

You are right. vtk_data.GetDataInformation(0).IsA("vtkUnstructuredGrid") does produce 0 as well. The reason why I asked was because I have the following script:

print(‘vtk_data’)
print(vtk_data.GetDataInformation().GetNumberOfPoints())

d3Filter = D3(Input=vtk_data)
d3Filter .UpdatePipeline()
print(‘d3Filter.GetDataInformation().GetNumberOfPoints()’)
print(d3Filter.GetDad3FiltertaInformation().GetNumberOfPoints()

fetch = servermanager.Fetch( d3Filter )
print('fetch.GetNumberOfPoints()

Output:

vtk_data
1203402
d3Filter.GetDataInformation().GetNumberOfPoints()
1305894
fetch.GetNumberOfPoints()
166927

It looks like the fetch function only fetch data from one rank. By looking at the fetch function source code here https://kitware.github.io/paraview-docs/latest/python/_modules/paraview/servermanager.html. I suspected the object I passed failed all the follow if statement check, and haven’t had a reduce operation.

    if cdinfo.GetDataIsComposite():
       paraview.print_debug_info("use composite data append")
       reducer.PostGatherHelperName = "vtkMultiBlockDataGroupFilter"

    elif input.GetDataInformation(idx).GetDataClassName() == "vtkPolyData":
       paraview.print_debug_info("use append poly data filter")
       reducer.PostGatherHelperName = "vtkAppendPolyData"

   elif input.GetDataInformation(idx).GetDataClassName() == "vtkRectilinearGrid":
     paraview.print_debug_info("use append rectilinear grid filter")
     reducer.PostGatherHelperName = "vtkAppendRectilinearGrid"

   elif input.GetDataInformation(idx).IsA("vtkDataSet"):
       paraview.print_debug_info("use unstructured append filter")
       reducer.PostGatherHelperName = "vtkAppendFilter"

Would that be because I am not passing the actual data?