Function CalcFeatureEffectAverageChange

catboost/libs/fstr/calc_fstr.cpp:94–144

}

TVector<std::pair<double, TFeature>> CalcFeatureEffectAverageChange(
    const TFullModel& model,
    TConstArrayRef<double> weights)
{
    if (model.GetTreeCount() == 0) {
        return TVector<std::pair<double, TFeature>>();
    }
    TVector<double> effect;
    TVector<TFeature> features;

    THashMap<TFeature, int, TFeatureHash> featureToIdx = GetFeatureToIdxMap(model, &features);
    if (model.IsOblivious()) {
        TVector<TMxTree> trees = BuildTrees(featureToIdx, model);

        TVector<TConstArrayRef<double>> mxTreeWeightsPresentation;
        auto applyData = model.ModelTrees->GetApplyData();
        auto leafOffsetPtr = applyData->TreeFirstLeafOffsets.data();
        const auto leafSizes = model.ModelTrees->GetModelTreeData()->GetTreeSizes();
        const int approxDimension = model.ModelTrees->GetDimensionsCount();
        for (size_t treeIdx = 0; treeIdx < model.GetTreeCount(); ++treeIdx) {
            mxTreeWeightsPresentation.push_back(
                TConstArrayRef<double>(
                    weights.data() + leafOffsetPtr[treeIdx] / approxDimension,
                    (1ull << leafSizes[treeIdx])
                )
            );
        }
        effect = CalcEffect(
            trees,
            mxTreeWeightsPresentation
        );
    } else {
        effect = CalcEffectForNonObliviousModel(
            model,
            featureToIdx,
            weights
        );
    }

    TVector<std::pair<double, int>> effectWithFeature;
    for (int i = 0; i < effect.ysize(); ++i) {
        effectWithFeature.emplace_back(effect[i], i);
    }
    StableSort(effectWithFeature.begin(), effectWithFeature.end(), std::greater<std::pair<double, int>>());

    TVector<std::pair<double, TFeature>> result;
    for (int i = 0; i < effectWithFeature.ysize(); ++i) {
        result.emplace_back(effectWithFeature[i].first, features[effectWithFeature[i].second]);
    }
    return result;
}

static TVector<std::pair<double, TFeature>> CalcFeatureEffectAverageChange(
    const TFullModel& model,