# Extract surface of domain based on condition

**URL:** https://discourse.paraview.org/t/extract-surface-of-domain-based-on-condition/4694
**Category:** ParaView Support
**Created:** [June 26, 2020, 1:21pm UTC](https://discourse.paraview.org/t/extract-surface-of-domain-based-on-condition/4694 "2020-06-26T13:21:58Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![thabuis](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/t/5f8ce5/32.png) [@thabuis](https://discourse.paraview.org/u/thabuis)
#### Post date: [June 26, 2020, 1:21pm UTC](https://discourse.paraview.org/t/extract-surface-of-domain-based-on-condition/4694/1 "2020-06-26T13:21:58Z")

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Hello everyone,

I have a .pvd file generated from FEniCS containing some data points.  
I would like to extract the cells/surfaces where a condition is met (data\_value \> 0.5), to export it afterwards to a .STL file. See the picture below as an example, I want to extract the red ring.

 ![data](https://discourse.paraview.org/uploads/default/original/2X/8/8d4660cc472ffbad02de84866fc1dac627cf3c0b.png)

However, when trying `Edit` --\> `Find Data`, I am only able to find points and cannot afterwards export the desired surface to STL.  
If I try to reconstruct the surface from the selected data points with a `Delaunay 2D` filter, the topological features (holes) are lost …

Do you have some suggestions on how should I proceed?  
Here are the corresponding files: [final\_solution.pvd](https://discourse.paraview.org/uploads/short-url/nO9uXkaXqDnvLaZNHqmoAVKmFql.pvd) (176 Bytes) [final\_solution000000.vtu](https://discourse.paraview.org/uploads/short-url/rT4YIGn2JybMk4W613VkXUL1FmR.vtu) (19.8 KB)

Thank you for your time.

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### Author: ![Kenichiro-Yoshimi](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/k/ecc23a/32.png) [@Kenichiro-Yoshimi](https://discourse.paraview.org/u/Kenichiro-Yoshimi)
#### Post date: [June 27, 2020, 11:33am UTC](https://discourse.paraview.org/t/extract-surface-of-domain-based-on-condition/4694/2 "2020-06-27T11:33:19Z")

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Hello,

Could you try the **Threshold** filter or the **Clip** filter with **Clip Type** (= Scalar)? Then apply the **Extract Surface** filter and save it to a STL format.

 ![clip_or_threshold](https://discourse.paraview.org/uploads/default/original/2X/c/c82db9dd45bed3c9ef6d9aeab666f72fe5dc7bde.png)

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### Author: ![thabuis](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/t/5f8ce5/32.png) [@thabuis](https://discourse.paraview.org/u/thabuis)
#### Post date: [June 29, 2020, 8:00am UTC](https://discourse.paraview.org/t/extract-surface-of-domain-based-on-condition/4694/3 "2020-06-29T08:00:50Z")

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This works perfectly  
Thank you very much!