# Extracting values 1m above a surface

**URL:** https://discourse.paraview.org/t/extracting-values-1m-above-a-surface/5547
**Category:** ParaView Support
**Created:** [October 12, 2020, 2:15pm UTC](https://discourse.paraview.org/t/extracting-values-1m-above-a-surface/5547 "2020-10-12T14:15:59Z")
**Posts on this page:** 4
**Page:** 1

<div class="post-metadata">

### Author: ![Jan\_Majcher](https://discourse.paraview.org/user_avatar/discourse.paraview.org/jan_majcher/32/5132_2.png) [@Jan\_Majcher](https://discourse.paraview.org/u/Jan_Majcher)
#### Post date: [October 12, 2020, 2:15pm UTC](https://discourse.paraview.org/t/extracting-values-1m-above-a-surface/5547/1 "2020-10-12T14:15:59Z")

</div>

Hi,

I have a solved OpenFoam case with a 3D seabed geometry embedded in a mesh using snappyHexMesh. I would like to extract flow velocities 1 m above the surface (1m higher than the surface in z direction at each cell), which are stored in internal mesh. I would like to simply build a slice which is 1 m higher than a surface at every point (cell), and then export the values to create an ASCII raster for GIS purposes. Is there an easy way to do it?

Cheers,  
Jan

---

<div class="post-metadata">

### Author: ![Jan\_Majcher](https://discourse.paraview.org/user_avatar/discourse.paraview.org/jan_majcher/32/5132_2.png) [@Jan\_Majcher](https://discourse.paraview.org/u/Jan_Majcher)
#### Post date: [November 4, 2021, 4:54pm UTC](https://discourse.paraview.org/t/extracting-values-1m-above-a-surface/5547/2 "2021-11-04T16:54:48Z")

</div>

As I have received a few private messages regarding the solution to this question, let me share my approach:

1. Export your surface to csv as points with coordinates
2. Add +1 or any other desired height above the surface to the column corresponding to the z coordinate
3. Import the csv to paraview, use table to points, set Z column = this is your z+1 column.
4. Resample with dataset. Your imported points are the destination dataset, the original internal mesh is the source data array.

Hope this helps somebody.

---

<div class="post-metadata">

### Author: ![fvg](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/f/8e7dd6/32.png) [@fvg](https://discourse.paraview.org/u/fvg)
#### Post date: [November 10, 2021, 1:24pm UTC](https://discourse.paraview.org/t/extracting-values-1m-above-a-surface/5547/3 "2021-11-10T13:24:53Z")

</div>

Good method, but it can be done even easier.

1. Import the ground surface as ply / stl / surface mesh (or extract surface within paraview)
2. transform upwards 1m
3. resample with dataset with transformed surface as destination mesh

Very useful to get the wind velocity at pedestrian level.

---

<div class="post-metadata">

### Author: ![Jan\_Majcher](https://discourse.paraview.org/user_avatar/discourse.paraview.org/jan_majcher/32/5132_2.png) [@Jan\_Majcher](https://discourse.paraview.org/u/Jan_Majcher)
#### Post date: [November 10, 2021, 2:51pm UTC](https://discourse.paraview.org/t/extracting-values-1m-above-a-surface/5547/4 "2021-11-10T14:51:29Z")

</div>

I like this, Frank… nice and easy.

Cheers,  
Jan