Hello, i’ll give some context first: Let \mathscr{P} be a partition of the domain \Omega into N_{E} disjoint open elements \Omega_{e} : \bar{\Omega}=\bigcup_{e=1}^{N_{E}} \bar{\Omega}_{e} \quad \text { and } \quad \Omega_{e} \cap \Omega_{f}=\emptyset \quad \text { for } e \neq f where \bar{\Omeg…

consider lamb = Constant(0) s_lamb = (1/2+lamb)*s("+")+(1/2-lamb)*s("-")

something along these lines? Keep in mind that if \lambda is also multivalued you’ll need to restrict it to the appropriate side of the facet. from dolfin import * mesh = UnitSquareMesh(1, 1) V = FunctionSpace(mesh, "CG", 1) s = interpolate(Constant(1.0), V) F1 = avg(s)*dS print(assemble(F1)) …

If you consistently mark the domains \Omega_e with a cell function, the the restrictions s("+") and s("-") is consistently ordered, as shown in: [image] Integrating over an interior surface variational formulation Hi, consider using restriction using + and -. Here foo('+')…

I’m not sure i understand what you mean by “consistently mark the domains with a cell function”, i’ve defined a mesh as a domain and some boundary markers as subdomains and wrote: ds = Measure('ds', domain=mesh, subdomain_data=boundary_markers) so my intention is to do something like: F = inner(a…

Please read the post I linked to for clarification and details. [image] dokken: as shown in:

I’m getting an error when i write: def norma2(u): return sqrt(dot(u,u) + DOLFIN_EPS) def avg_gamma(u, gamma): return (0.5+gamma("+"))*u("+") + (0.5-gamma("-"))*u("-") lbda = conditional(gt(dot(u,ν),0),0.5*dot(u,ν)/abs(dot(u,ν)),0) θ=0.5 H=η+h H_n=η_n+h B = inner((η-η_out)/(2*k),ϕ)*dx + in…

I think the error i get may not be related to this, i’ll make a new post. Thanks!

Defining weighted averages

variational formulation

dokken December 7, 2021, 11:01am 8

Please make a minimal example; as described in: Read before posting: How do I get my question answered?

Topic		Replies	Views
How to compute the average value of u of a part of the domain and of a facet? variational formulation	2	816	February 29, 2020
Strange behavior of average of two functions General	0	26	September 29, 2024
Normal unit vector in variational formulation variational formulation	1	824	July 23, 2020
Integrating over an interior surface variational formulation	23	8092	October 18, 2024
Correctly setting initial conditions using Expression() in DG problem Legacy DOLFIN dg	4	183	June 12, 2024

Defining weighted averages

Related topics