# How not to output InformationKey when data is output to vtu

**URL:** https://discourse.vtk.org/t/how-not-to-output-informationkey-when-data-is-output-to-vtu/11552
**Category:** Support
**Tags:** python
**Created:** [May 27, 2023, 4:14pm UTC](https://discourse.vtk.org/t/how-not-to-output-informationkey-when-data-is-output-to-vtu/11552 "2023-05-27T16:14:40Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![xiaojinyu-hhu](https://discourse.vtk.org/user_avatar/discourse.vtk.org/xiaojinyu-hhu/32/7151_2.png) [@xiaojinyu-hhu](https://discourse.vtk.org/u/xiaojinyu-hhu)
#### Post date: [May 27, 2023, 4:14pm UTC](https://discourse.vtk.org/t/how-not-to-output-informationkey-when-data-is-output-to-vtu/11552/1 "2023-05-27T16:14:40Z")

</div>

I output data to .vtu with vtkXMLUnstructuredGridWriter.  
However, VTU files always have  
InformationKey name=“L2\_NORM\_RANGE” location=“vtkDataArray” length=“2”  
Value index=“0”  
0  
Value  
Value index=“1”  
1.1661903912  
Value  
InformationKey  
I don’t want to output InformationKey. How can I not output it?

```auto
from vtkmodules.vtkIOXML import vtkXMLDataSetWriter
from vtkmodules.vtkCommonCore import vtkPoints
import vtkmodules
from vtkmodules.vtkCommonCore import *
from vtkmodules.util import numpy_support
import numpy

if __name__ == ' __main__':
    position = vtkPoints()
    position.SetDataType(VTK_FLOAT)
    position.InsertNextPoint(0, 0, 0)
    position.InsertNextPoint(1, 0, 0)
    position.InsertNextPoint(0, 1, 0)
    position.InsertNextPoint(0, 0, 1)
    position.InsertNextPoint(1, 0, .4)
    position.InsertNextPoint(0, 1, .6)

    grid = vtkmodules.vtkCommonDataModel.vtkUnstructuredGrid()
    grid.SetPoints(position)
    data = numpy.arange(0, 6, 1)
    data = numpy_support.numpy_to_vtk(data)
    data.SetName("pressure")
    grid.GetPointData().AddArray(data)

    writer = vtkmodules.vtkIOXML.vtkXMLUnstructuredGridWriter()
    #writer.SetDataModeToAppended()
    writer.SetDataMode(writer.Ascii)
    writer.SetFileName('a.vtu')
    writer.SetInputData(grid)
    writer.Write()

```