private static Map computeStats()

in modules/ml-ext/ml/src/main/java/org/apache/ignite/ml/selection/scoring/evaluator/Evaluator.java [556:608]
46 lines of code
12 McCabe index (conditional complexity)

    private static <K, V> Map<Class, MetricStatsAggregator> computeStats(IgniteModel<Vector, Double> mdl,
        Dataset<EmptyContext, FeatureMatrixWithLabelsOnHeapData> dataset, IgniteCache<K, V> cache,
        Preprocessor<K, V> preprocessor,
        Map<Class, EvaluationContext> ctxs, Metric... metrics) {

        if (isOnlyLocalEstimation(mdl) && cache != null) {
            Map<Class, MetricStatsAggregator> aggrs = initAggregators(ctxs, metrics);

            try (QueryCursor<Cache.Entry<K, V>> qry = cache.query(new ScanQuery<>())) {
                qry.iterator().forEachRemaining(kv -> {
                    LabeledVector vector = preprocessor.apply(kv.getKey(), kv.getValue());

                    for (Class key : aggrs.keySet()) {
                        MetricStatsAggregator aggr = aggrs.get(key);
                        aggr.aggregate(mdl, vector);
                    }
                });
            }

            return aggrs;
        }
        else {
            return dataset.compute(data -> {
                Map<Class, MetricStatsAggregator> aggrs = initAggregators(ctxs, metrics);

                for (int i = 0; i < data.getLabels().length; i++) {
                    LabeledVector<Double> vector = VectorUtils.of(data.getFeatures()[i]).labeled(data.getLabels()[i]);
                    for (Class key : aggrs.keySet()) {
                        MetricStatsAggregator aggr = aggrs.get(key);
                        aggr.aggregate(mdl, vector);
                    }
                }

                return aggrs;
            }, (left, right) -> {
                if (left == null && right == null)
                    return new HashMap<>();
                if (left == null)
                    return right;
                if (right == null)
                    return left;

                HashMap<Class, MetricStatsAggregator> res = new HashMap<>();
                for (Class key : left.keySet()) {
                    MetricStatsAggregator agg1 = left.get(key);
                    MetricStatsAggregator agg2 = right.get(key);
                    A.ensure(agg1 != null && agg2 != null, "agg1 != null && agg2 != null");
                    res.put(key, agg1.mergeWith(agg2));
                }
                return res;
            });
        }
    }