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["Garth N. Wells" <gnw20@xxxxxxxxx>]

Kristian Oelgaard wrote:
> Hello,
>
> Given the new Function interface, is it possible to get a reference to the part
> of the Function vector belonging to a SubFunction?

No.

> GenericVector* U0 = &U[0].vector(); (this doesn't work)
>
> I need to inspect the solution values in a Newton solve and set any negative
> values to zero.

If you do

  Function U0 = U[0];

the Function U0 will have a copy of part of the vector that belongs to 
U, therefore changing the vector that belongs to U0 won't affect the 
vector that belongs to U.

Take a look inside

  Function::Function(const SubFunction& v)

to see how to determine which components of the vector are associated 
with a particular subspace. This way, you can work with the Function U 
directly.

Garth


> Kristian
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