# Tag Info

Accepted

### Estimating forces on a model from the displacements of nodes

Indeed, as @whpowell96 says, we can use optimization. Let us assume, for simplicity that your problem is governed by the equations of linear elasticity. Let us assume that you have displacement data (...
• 654
Accepted

### C^1 continuous element for a triangle?

tl;dr: defelement link There is an equivalence between all polynomial basis which span the same space so in theory you can use the standard monomial basis to fit the various parameters using a ...
• 1,741

### C^1 continuous element for a triangle?

The $C^1$ elements are all very challenging to implement, which is why you don't see them get used very often. If you just want to see what the basis functions are on the reference (or other) ...
• 9,013
Accepted

### FreeFEM++ converting equation into code

In the piece of code that you mentioned from the FreeFEM documentation, the Galerkin Finite Element Method (FEM) is used for the spatial discretization and the Finite Difference Method (FDM) is used ...
• 194
1 vote
Accepted

### Solving a boundary value problem with variable number of coupled equations

This is a situation where some variables only live on parts of the domain. This is not so different from multiphysics problems -- say, a fluid-structure interaction problem where velocity and pressure ...
• 52.4k
### How to compute numerically the $H^{1/2}$ norm of a function
I think what you are referring to is $\|h^{-1/2}g\|_{0,\partial D}$. The point is that it can be though of as the 'discrete' $H^{1/2}$ norm. It comes down to the so called 'inverse inequalities' where ...