compute L2 error

How to compute the error over a subdomain ?

Hello Wen Jing,

have a Look at the tutorial on subdomains you see that bilinear forms use the `definedon` to determine which domain to act on If you look at the docstring of the Integrate function you will see that is also has an optional Flag 'definedon' which you can use just as as in a BilinearForm to integrate over a subdomain.

Best wishes
Henry

Thanks for your reply. I tried “ erru3 = sqrt( Integrate(errDD,mesh,order = 2*order, definedon=[2]) )” , but it doesn't seem to be able to use it that way.

TypeError: Integrate(): incompatible function arguments. The following argument types are supported:

`definedon` expects a ngsolve.Region object (as stated in the docstring) so you need to give is something like mesh.Materials("region_name")

Thanks for your help!

Best regards,
Wen jing

We can compute the error of the subregion, so can we graph the solution on the subregion? If yes, could you give me a general idea? Looking for your reply, thanks!

Best regards,
Wen Jing