code: public static Pair<O1DpHypergraph, Scores> insideSingleRootEntropyFoe(double[] fracRoot, double[][] fracChild) {
          final Algebra semiring = LogSignAlgebra.getInstance();         
          return insideSingleRootEntropyFoe(fracRoot, fracChild, semiring);
      }
docs: Runs the inside-outside algorithm for dependency parsing.
  
  @param fracRoot Input: The edge weights from the wall to each child.
  @param fracChild Input: The edge weights from parent to child.
  @return The parse chart.