# PolyData vtp XML file, problems assigning Custom Properties to cells

**URL:** https://discourse.paraview.org/t/polydata-vtp-xml-file-problems-assigning-custom-properties-to-cells/17201
**Category:** ParaView Support
**Tags:** vtk
**Created:** [September 23, 2025, 10:22am UTC](https://discourse.paraview.org/t/polydata-vtp-xml-file-problems-assigning-custom-properties-to-cells/17201 "2025-09-23T10:22:29Z")
**Posts on this page:** 3
**Page:** 1

<div class="post-metadata">

### Author: ![Dumisani\_D](https://discourse.paraview.org/user_avatar/discourse.paraview.org/dumisani_d/32/17024_2.png) [@Dumisani\_D](https://discourse.paraview.org/u/Dumisani_D)
#### Post date: [September 23, 2025, 10:22am UTC](https://discourse.paraview.org/t/polydata-vtp-xml-file-problems-assigning-custom-properties-to-cells/17201/1 "2025-09-23T10:22:29Z")

</div>

Hi Community,

I am having a challenge loading a .vtp file in Paraview. The attached .vtp file below has 6 Polygons, their corresponding points and cells. The mesh loads correctly when I ommit the CellData tag, however, the following error occurs when I try to assign a scalar or vector to each cell. Could anyone assist with check what could be wrong with the simple .vtp file below that I generated. Thanks in advance.

 ![image](https://discourse.paraview.org/uploads/default/original/3X/b/3/b311393950df3c91148115d4b9a8a6e5d9316bcb.png)

Steps to reproduce:

1. Load the .vtp file below
2. Click Apply on the properties section
3. Display the file in the Pipeline Browser

\<?xml version='1.0'?\> 

```
<Piece NumberOfPoints="24" NumberOfVerts="24" NumberOfLines="0" NumberOfStrips="0" NumberOfPolys="6">

  <Points>

    <DataArray type="Float32" NumberOfComponents="3" format="ascii">0.0 -0.5 0.0 0.0 0.5 0.0 -8.0 0.5 0.0 -8.0 -0.5 0.0 0.0 0.0 0.5 0.0 0.0 -0.5 -8.0 0.0 -0.5 -8.0 0.0 0.5 0.0 -0.5 0.0 0.0 0.5 0.0 -8.0 0.5 0.0 -8.0 -0.5 0.0 0.0 0.0 0.5 0.0 0.0 -0.5 -8.0 0.0 -0.5 -8.0 0.0 0.5 0.0 -0.5 0.0 0.0 0.5 0.0 -8.0 0.5 0.0 -8.0 -0.5 0.0 0.0 0.0 0.5 0.0 0.0 -0.5 -8.0 0.0 -0.5 -8.0 0.0 0.5</DataArray>

  </Points>

  <Polys>

    <DataArray type="Int32" Name="connectivity" format="ascii">0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23</DataArray>

    <DataArray type="Int32" Name="offsets" format="ascii">4 8 12 16 20 24</DataArray>

  </Polys>

  <CellData>

    <DataArray type="Float32" Name="property_a" NumberOfComponents="1" format="ascii">0.0 0.0 0.0 0.0 0.0 0.0</DataArray>

    <DataArray type="Float32" Name="property_b" NumberOfComponents="1" format="ascii">0.1158 0.1158 0.27175 0.27175 0.27175 0.27175</DataArray>

    <DataArray type="Float32" Name="property_c" NumberOfComponents="1" format="ascii">0.8842 0.8842 0.72825 0.72825 0.72825 0.72825</DataArray>

  </CellData>

</Piece>

```

[model\_vtp\_generated.vtp](https://discourse.paraview.org/uploads/short-url/rxBJZIRUcAM9Ikb4pGSAWDNI00Z.vtp) (1.4 KB)

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<div class="post-metadata">

### Author: ![mwestphal](https://discourse.paraview.org/user_avatar/discourse.paraview.org/mwestphal/32/17_2.png) [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [September 24, 2025, 9:10am UTC](https://discourse.paraview.org/t/polydata-vtp-xml-file-problems-assigning-custom-properties-to-cells/17201/2 "2025-09-24T09:10:22Z")

</div>

` NumberOfVerts="24"`

should be

`NumberOfVerts="0"`

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<div class="post-metadata">

### Author: ![Dumisani\_D](https://discourse.paraview.org/user_avatar/discourse.paraview.org/dumisani_d/32/17024_2.png) [@Dumisani\_D](https://discourse.paraview.org/u/Dumisani_D)
#### Post date: [September 25, 2025, 9:50am UTC](https://discourse.paraview.org/t/polydata-vtp-xml-file-problems-assigning-custom-properties-to-cells/17201/3 "2025-09-25T09:50:12Z")

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Thank you, this solved the problem.