Hello, I am using legacy Fenics. Given a function defined on a mesh, I would like to extract its values only on the points which belong to the mesh boundary. I have looked online for this, all I could find is either answers how to define a class which defines a boundary which is then used in Dir…

Following your link, I found a solution by using a dummy space of polynomials with one degree, here it is. This function returns the coordinates of the boundary points of a mesh, then the nodal values of a function (even if this function is defined on a polynomial space with degree larger than one) …

Extract the nodal values of a function on the boundary of the mesh

General

dokken January 24, 2025, 10:05am 2

See for instance: Question on Dolfin poisson equation for source measurement on borders - #26 by dokken

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Extract the nodal values of a function on the boundary of the mesh

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