/** Optimize this grammar node. */
public void Optimize()
{
for (int i = 0; i < _arcList.Count; i++)
{
GrammarArc arc = _arcList[i];
_arcList[i] = OptimizeArc(arc);
}
// now remove all self-looping empty arcs
if (IsEmpty)
{
for (Int16 i = 0; i < _arcList.Count; i++)
{
if (i > _arcList.Count - 2)
{
break;
}
GrammarArc arc = _arcList[i + 1];
if (this == arc.GrammarNode)
{
_arcList.RemoveAt(i);
}
}
}
}
/**
* /// Optimize the given arc. If an arc branches to an empty node that has only one exit, the node can be bypassed by
* /// making a new arc that skips the nodes. This can happen multiple times.
*
* /// @param arc the arc to optimize
* /// @return the optimized arc
*/
GrammarArc OptimizeArc(GrammarArc arc)
{
GrammarNode nextNode = arc.GrammarNode;
while (nextNode.IsEmpty && nextNode._arcList.Count == 1)
{
GrammarArc nextArc = nextNode._arcList[0];
arc = new GrammarArc(nextArc.GrammarNode,
arc.Probability + nextArc.Probability);
nextNode = arc.GrammarNode;
}
return(arc);
}
