Method visit

JSAT/src/jsat/classifiers/trees/MDI.java:85–134

(TreeNodeVisitor node, ImpurityScore score, List<DataPointPair<Integer>> data, final double[] features , final double N, final int K)

    }
    
    private void visit(TreeNodeVisitor node, ImpurityScore score, List<DataPointPair<Integer>> data, final double[] features , final double N, final int K)
    {
        if (node == null || node.isLeaf() )//invalid path or no split, so skip
            return;
        
        double curScore = score.getScore();
        double curN = score.getSumOfWeights();
        
        //working space to split data up into new subsets
        List<List<DataPointPair<Integer>>> splitsData = new ArrayList<List<DataPointPair<Integer>>>(node.childrenCount());
        List<ImpurityScore> splitScores = new ArrayList<ImpurityScore>(node.childrenCount());
        splitsData.add(data);
        splitScores.add(score);
        for(int i = 0; i < node.childrenCount()-1; i++)
        {
            splitsData.add(new ArrayList<DataPointPair<Integer>>());
            splitScores.add(new ImpurityScore(K, im));
        }
        
        //loop through and split up our data
        for(ListIterator<DataPointPair<Integer>> iter = data.listIterator(); iter.hasNext();)
        {
            DataPointPair<Integer> curPoint = iter.next();
            final int tc = curPoint.getPair();
            DataPoint dp = curPoint.getDataPoint();
            int path = node.getPath(dp);
            if(path < 0)//NaN will cause -1
                score.removePoint(dp, tc);
            else if(path > 0)//0 will be cur data and score obj, else we move to right location
            {
                score.removePoint(dp, tc);
                splitScores.get(path).addPoint(dp, tc);
                splitsData.get(path).add(curPoint);
                iter.remove();
            }
        }
        
        double chageInImp = curScore;
        for(ImpurityScore s : splitScores)
            chageInImp -= s.getScore()*(s.getSumOfWeights()/(1e-5+curN));
        
        
        Collection<Integer> featuresUsed = node.featuresUsed();
        for (int feature : featuresUsed)
            features[feature] += chageInImp*curN/N;

        //now visit our children
        for(int path = 0; path < splitScores.size(); path++)
            visit(node.getChild(path), splitScores.get(path), splitsData.get(path), features, N, K);
    }
    
}