XMDF: Error, no proxy that matches: group= and proxy= were found.

[Nico Schlömer]

When writing data to an XDMF file, the file is not recognized as XDMF3 by ParaView.

Example:

import dolfin

mesh = dolfin.UnitSquareMesh(10, 1)
V = dolfin.FunctionSpace(mesh, 'CG', 1)
u = dolfin.Function(V)

with dolfin.XDMFFile('test.xdmf') as xdmf_file:
    xdmf_file.write(u)

Resulting file (without the heavy data):

<?xml version="1.0"?>
<Xdmf Version="3.0">
  <Domain>
    <Grid Name="mesh" GridType="Uniform">
      <Topology NumberOfElements="20" TopologyType="Triangle" NodesPerElement="3">
        <DataItem Dimensions="20 3" NumberType="UInt" Format="HDF">test.h5:/Mesh/mesh/topology</DataItem>
      </Topology>
      <Geometry GeometryType="XY">
        <DataItem Dimensions="22 2" Format="HDF">test.h5:/Mesh/mesh/geometry</DataItem>
      </Geometry>
      <Attribute Name="f_4" AttributeType="Scalar" Center="Node">
        <DataItem Dimensions="22 1" Format="HDF">test.h5:/VisualisationVector/0</DataItem>
      </Attribute>
    </Grid>
  </Domain>
</Xdmf>

When trying to open with ParaView:

ERROR: In /home/buildslave/dashboards/buildbot/paraview-pvbinsdash-linux-shared-release_superbuild/source-paraview/ParaViewCore/ServerImplementation/Core/vtkSIProxyDefinitionManager.cxx, line 526
vtkSIProxyDefinitionManager (0x2590e60): No proxy that matches: group= and proxy= were found.

The file does open as XDMF(2), but since support for that will be removed from ParaView soon, this will become urgent.

[Michal Habera]

What setting do you use? I do not have a problem running the snippet and reading on master and ParaView 5.4.0.

[Nico Schlömer]

I'm using dolfin on master and ParaView 5.4.0. I've also simplified the original example. The heavy data is here.

Do you get the same XML?

[Nico Schlömer]

Ah wait, in ParaView, do you choose, Xdmf3 Reader or Xdmf3 Reader (Top Level Partition)?

[Michal Habera]

Xdmf3 Reader, but it works on any reader I choose, even Xdmf(2) (strange). From dolfin I get the same XML file. More specifically I have 5.4.0-RC2 64-bit. This is probably an issue of ParaView.

[Nico Schlömer]

Sounds like it. I opened a bug for ParaView https://gitlab.kitware.com/paraview/paraview/issues/17594.