pvd: time series with multiple datasets

Question

I am using .pvd file to load multiple files to Paraviw simultaneously. The file looks like this for time-series with a a single dataset:

<?xml version="1.0"?>
<VTKFile type="Collection" version="0.1">
  <Collection>
    <DataSet timestep="0" file="a.1.vtu"/>
    <DataSet timestep="1" file="a.2.vtu"/>
  </Collection>
</VTKFile>

I would like to specify other files to be loaded along with a.*.vtu (e.g. b.*.vtp) which will show up as another item in the pipeline browser.

I tried to put multiple <Collection> blocks to the .vtp, but Paraview loads only one of them. I also tried using group and part attributes to <DataSet>, without any result.

How can I achieve having separate datasets (all of them saved at the same points in time) in one .pvd file?

Answer 1

You can't. To create separate items in the pipeline browser, you need to open separate files i.e. create separate pvd files for a..vtu and b..vtu with same timestep values and the UI will still load the same timestep at a time from both the files when playing animations etc.