Evaluating Solution at Arbitrary Points

General Discussion
1

Dear FreeFEM users and developers,

I am trying to evaluate the value of a solution at a specific point in order to compare it with a theoretical value. If the point lies exactly on a mesh node, the method described in this post works well.

However, if the point does not coincide with a mesh node, interpolation is necessary. I would like to ask whether FreeFEM provides any built-in functionality to perform this kind of interpolated evaluation at arbitrary spatial points.

Thank you in advance for your help.

2

Yes, it does, it’s explained in the manual.

1 Like
3

Thanks. I also got it from AI. I was just surprised since AI couldn’t give a correct answer about FreeFem++ a few months ago.

real value;
value = uh(x_coord, y_coord);

4

That code is wrong, yet another example of wrongful use of AI.