# Is there any simple to compute do product between cell normal and a vector like vtkVectorDot
**URL:** https://discourse.vtk.org/t/is-there-any-simple-to-compute-do-product-between-cell-normal-and-a-vector-like-vtkvectordot/7608
**Category:** Support
**Created:** [January 10, 2022, 6:26am UTC](https://discourse.vtk.org/t/is-there-any-simple-to-compute-do-product-between-cell-normal-and-a-vector-like-vtkvectordot/7608 "2022-01-10T06:26:27Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@AlexLuya](https://discourse.vtk.org/u/AlexLuya)
#### Post date: [January 10, 2022, 6:26am UTC](https://discourse.vtk.org/t/is-there-any-simple-to-compute-do-product-between-cell-normal-and-a-vector-like-vtkvectordot/7608/1 "2022-01-10T06:26:27Z")
Hello,vtkVectorDot can be used to compute the dot product between POINT normal and vectors,any similar way for CELL normals?
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### Author:  [@will.schroeder](https://discourse.vtk.org/u/will.schroeder)
#### Post date: [January 10, 2022, 1:14pm UTC](https://discourse.vtk.org/t/is-there-any-simple-to-compute-do-product-between-cell-normal-and-a-vector-like-vtkvectordot/7608/2 "2022-01-10T13:14:24Z")
Interesting, that filter could easily be modified to operate on cell data as well. Do you want to try submitting a MR?
Also, you could use one of the VTK programmable filters to do the same thing. And possibly even the vtkArrayCalculator, although I am not sure about this since I don’t use the filter that often.
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### Author:  [@AlexLuya](https://discourse.vtk.org/u/AlexLuya)
#### Post date: [January 10, 2022, 1:26pm UTC](https://discourse.vtk.org/t/is-there-any-simple-to-compute-do-product-between-cell-normal-and-a-vector-like-vtkvectordot/7608/3 "2022-01-10T13:26:01Z")
Thanks,I will try to find an example about vtkArrayCalculator,and submit MR