# Activation Order in Parameter Files

Issue #705 resolved
Steven R. Brandt created an issue

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:

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

• removed milestone
• removed comment
• removed comment

• removed comment

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.

• removed comment

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?

2. reporter
• removed comment

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.

• removed comment

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).