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4.1.5 Symbolic Constants and Variables (VarConstDeclaration)

Between the declaration parts for neighbours and the boundary value, there is now space left to define variables and symbolic constants, if there is a need of it. Otherwise this part can be omitted.

together with
 

and
 

We are not going to give a description of how to use this syntax, because it is exactly the same as in RDL, where we have already discussed it. So please refer to these pages as well as to the paragraphs about symbolic constants and variables in general to get further information.

There is but one thing special for SDL: while variables are initialized after each change of site the local rule is applied to, symbolic constants keep their values during the whole simulation, so that neighbours used as symbolic constants have no meaning here (compare to 'Local Rule Table'). That is the reason why neither in RDL nor in SDL it is allowed to use elements of NeighbourIdentifier in this part.

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