# Adding new partially quadratic element (Hexahedron with 10 nodes) to VTK

**URL:** <https://discourse.vtk.org/t/adding-new-partially-quadratic-element-hexahedron-with-10-nodes-to-vtk/15846>\
**Category:** Development\
**Created:** [July 21, 2025, 6:14am UTC](https://discourse.vtk.org/t/adding-new-partially-quadratic-element-hexahedron-with-10-nodes-to-vtk/15846 "2025-07-21T06:14:34Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![jayeshsingh1110](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/j/b5ac83/32.png) [@jayeshsingh1110](https://discourse.vtk.org/u/jayeshsingh1110)\
**Post date:** [July 21, 2025, 6:14am UTC](https://discourse.vtk.org/t/adding-new-partially-quadratic-element-hexahedron-with-10-nodes-to-vtk/15846/1 "2025-07-21T06:14:34Z")

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I am trying to add a new type of cell to VTK to handle partially quadratic elements.

Using below image for reference:

 ![image](https://discourse.vtk.org/uploads/default/original/2X/f/f3f353c29a4804e2ff8cac984399757928ad343b.png)

One of the case :  
I would like in addition to linear nodes of this element (which are from 0 to 7), additional only two nodes are present (let’s say 16 & 17). Thus only 10 nodes of the 20 nodes are present in the element. How would I implement the class?

I know I would have to derive the new class from vtkNonLinearCell and implement the required methods. But I wanted to know how would I divide the geometry to get fully linear sub components (is it through three wedges or some other way). I see that the Quadratic Hexahedron is also divided into Linear Hexs, is there a strategy behind it? Also are there any documentation for this implementation?