6:53 AM
@xzczd hello there

7:14 AM
@zhk Hello

7:36 AM
@xzczd I am getting empty plot

https://www.dropbox.com/s/4l24gltlyfbqhyk/v%20sheet%201.nb?dl=0

@zhk I'm still in v9 so can't run the code, but I think it's because, it should be `ParametricNDSolveValue` rather than `ParametricNDSolve`
Also, `sol[#][1, zeta] &@{0, 0.5, 1}` should be `sol[#][1, zeta] &/@{0, 0.5, 1}//Evaluate`

@xzczd thx it worked just fine.

And, the interpretation for the robin boundary condition is wrong, I think

@xzczd I was suppose to ask this but you already said it
so where i went wrong?

7:55 AM
@zhk After checking the document carefully, I think it's correct 囧

@xzczd I followed C.E. suggestion to input these conditions
@zhk First, do you have any reason to believe that your answer is wrong. If so, why? Second, you have the boundary condition du/dx = -u[x], why would you not have du/dx = NeumannValue[-u[x, y], x==1] instead of NeumannValue[u[x, y], x==1] ?

@zhk This depends on the direction of outer normal vector

@xzczd Thx for your feed back.

See the Detail of Neumann condition

@xzczd OK i will thx

8:03 AM
You're welcome

@xzczd this the actual condition

8:33 AM
@zhk Wait, there exists something troublesome.
Now I should say I'm not sure what's the correct interpretation of the robin condition when `"FiniteElement"` method is used for the equation.
It's not clear to me how `epsilon` is handled inside `NDSolve` when `"FiniteElement"` is used.
I think it's better to ask this in the main site.

9:01 AM
@xzczd ok