Activation Order in Parameter Files

[Steven R. Brandt]

At the moment the ActiveThorns list is sensitive to the order in which thorns are activated if the ActiveThorns parameter is updated multiple times. However, it is not sensitive to the order in which thorns are activated if all thorns are specified in a single line. This inconsistency should be removed, and the order should not matter in either case.

Keyword:

[Frank Löffler]

Would be nice, but not for the next release anymore.

[Frank Löffler]

Isn't this now already order-independent?

[Roland Haas]

If you have several ActiveThorns lines in your parfile then the order matters. Ie.

ActiveTHorns = "CarpetLib"
Carpet::max_refinement_levels = 1
ActiveTorns = "Carpet"

fails as well as

ActiveTorns = "Carpet"
ActiveTHorns = "CarpetLib"

while

ActiveTorns = "Carpet
               CarpetLib"

is fine.

[Frank Löffler]

I know that this used to be the case, but Steve told me that piraha actually combines all ActiveThorns requests into one. What I don't know right now is whether that is in trunk already, or still in its own branch. Steve?

[Steven R. Brandt]

As Frank said. Since Piraha, the order should no longer matter. Piraha combines all the ActiveThorn declarations into one before passing it through to Cactus.

[Erik Schnetter]

The Cactus documentation says:

\item{} The parameter file is read \emph{sequentially} from top to bottom,
        this means that if you set the value of a parameter twice in
        the parameter file, the second value will be used. (This is
        why the \texttt{ActiveThorns} parameter is always first in the file).

Please update this.

There are also many instances in the users' guide which speak of ActiveThorns as "the first parameter being set". If we allow this to be set multiple times, and if this is commonly used, then this should be mentioned as well.