DefineNeighbors[A,B]

DefineNeighbors[{A1,B1}, ..., {An,Bn}]

A,A1, ..., An: names of declared observers

B,B1, ..., Bn: names of declared observers

The function DefineNeighbors declares a direct relation between pairs of declared observers. Direct relations may not be declared between indirectly related observers.

The function DefineNeighbors results in permanent changes to the global variable GlobalObserverDeclarations.

Restart;
DeclareObservers[A,B,C];
DefineNeighbors[{A,B},{A,C}];
GlobalObserverDeclarations

$\left\{A\to \left\{B,C\right\},B\to \left\{A\right\},C\to \left\{A\right\}\right\}$

DeclareObservers, DefineObservers

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