# How to set a a dynamic DoubleVectorProperty in xml?

**URL:** https://discourse.paraview.org/t/how-to-set-a-a-dynamic-doublevectorproperty-in-xml/9245
**Category:** ParaView Support
**Created:** [March 21, 2022, 8:58pm UTC](https://discourse.paraview.org/t/how-to-set-a-a-dynamic-doublevectorproperty-in-xml/9245 "2022-03-21T20:58:19Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![Cam](https://discourse.paraview.org/user_avatar/discourse.paraview.org/cam/32/8343_2.png) [@Cam](https://discourse.paraview.org/u/Cam)
#### Post date: [March 21, 2022, 8:58pm UTC](https://discourse.paraview.org/t/how-to-set-a-a-dynamic-doublevectorproperty-in-xml/9245/1 "2022-03-21T20:58:19Z")

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I would like to define a property in the server xml for my filter like this.

```auto
      <DoubleVectorProperty name="MyPoints">
     </DoubleVectorProperty>

```

MyPoints is a dynamic array (new double[size]) and I update MyPoints in `RequestData` .  
Then, on the ParaView layer I can extract it like this.

```auto
        vtkSMDoubleVectorProperty* points =
                vtkSMDoubleVectorProperty::SafeDownCast(source->getProxy()->GetProperty("MyPoints"));

```

Is it possible to do something like this?

Thanks,  
Cam

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### Author: ![utkarsh.ayachit](https://discourse.paraview.org/user_avatar/discourse.paraview.org/utkarsh.ayachit/32/39_2.png) [@utkarsh.ayachit](https://discourse.paraview.org/u/utkarsh.ayachit)
#### Post date: [March 21, 2022, 10:52pm UTC](https://discourse.paraview.org/t/how-to-set-a-a-dynamic-doublevectorproperty-in-xml/9245/2 "2022-03-21T22:52:52Z")

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I’d start by looking at something else that does similar … `RGBPoints` on LookupTable proxy comes to mind…follow that pattern.

```xml
....
       <DoubleVectorProperty clean_command="RemoveAllPoints"
                            command="AddRGBPoint"
                            name="RGBPoints"
                            number_of_elements_per_command="4"
                            repeat_command="1"
                            number_of_elements="12"
                            default_values="0 0.231373 0.298039 0.752941 0.5 0.865003 0.865003 0.865003 1 0.705882 0.0156863 0.14902">
        <Documentation>
          Specify the control points that form the color-transfer-function. These are
          a list of 4-tuples of the form (x, r, g, b) where x is the data value,
          and r,g,b are three color components in the range [0,1].
        </Documentation>
      </DoubleVectorProperty>

```

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<div class="post-metadata">

### Author: ![Cam](https://discourse.paraview.org/user_avatar/discourse.paraview.org/cam/32/8343_2.png) [@Cam](https://discourse.paraview.org/u/Cam)
#### Post date: [March 21, 2022, 11:10pm UTC](https://discourse.paraview.org/t/how-to-set-a-a-dynamic-doublevectorproperty-in-xml/9245/3 "2022-03-21T23:10:25Z")

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Thank you Utkarsh. This is a really good example.