evaluateCGradient ,, trying find normal vector

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raed alraidmanuon 2020-9-21

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评论： raed alraidmanuon 2020-10-10

Hi

I would get the outward normal vector for at a boundary where I have a solution by pde. I have used 'evaluate Gradient' but unfortunately I have no idea to get the normal vector of the boundary.

Thanks

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Answer 1

Aman Vyas 2020-10-8

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Hi,

I think you can break this problem in two parts.

1) Detecting the boundary of the surface, object etc.

2) Finding the normal on the boundary.

Sinc you have solution from PDE, you will have exact information of boundary conditions using boundary function. Once you have boundary available apply evaluateCGradient which gives flux of the PDE. Flux actually flows as outward normal vector to the surface and thus this function will help you get the normal vector.

There are various features available in this function. You can take a look at this link:

https://www.mathworks.com/help/pde/ug/pde.stationaryresults.evaluatecgradient.html

Hope it helps !