How to measure roughness of a curved surface in matlab?

Hi all,

I'm trying to measure the areal surface roughness Sq of a curved surface, and I want to get rid of the waveness of the surface first and then use std() function.

Can someone please help substracting the waveness from the surface? I've attached the surface data (.mat).

Thanks in advance!

and the surface looks like this:

[darova]

What about smoothing?

Answer 1

[SaiDileep Kola]

check the similar question here