[Paraview] xdmf: JOIN() to create vector-field

[Jens]

Hi,

I am using xdmf for scalar fields until now. To create a vector-field
from my scalars I use the paraview calculator.

but I read that creating a vector with 3 scalars should be possible
directly in the xdmf-file.

I tried this, but it fails in paraview 3.4.0

<Attribute Active="1" Type="Vector" Center="Node" Name="gnorm">
  <DataItem ItemType="Function" Function="JOIN($0, $1, $2)">
     <DataItem ItemType="Uniform" Format="HDF"
       NumberType="Float" Precision="8" Dimensions
       &DataFile;:/g/data/ngx
     </DataItem>
     <DataItem ItemType="Uniform" Format="HDF"
       NumberType="Float" Precision="8" Dimensions
       &DataFile;:/g/data/ngy
     </DataItem>
     <DataItem ItemType="Uniform" Format="HDF"
       NumberType="Float" Precision="8" Dimensions
       &DataFile;:/g/data/ngz
     </DataItem>
  </DataItem>
</Attribute>

Any idea what I am doing wrong?

Greetings
Jens