Function CalcInternalFeatureInteraction

catboost/libs/fstr/calc_fstr.cpp:314–341

}

TVector<TInternalFeatureInteraction> CalcInternalFeatureInteraction(const TFullModel& model) {
    if (model.GetTreeCount() == 0) {
        return TVector<TInternalFeatureInteraction>();
    }
    CB_ENSURE_SCALE_IDENTITY(model.GetScaleAndBias(), "feature interaction");

    TVector<TFeature> features;
    THashMap<TFeature, int, TFeatureHash> featureToIdx = GetFeatureToIdxMap(model, &features);

    TVector<TFeaturePairInteractionInfo> pairwiseEffect;

    if (model.IsOblivious()) {
        TVector<TMxTree> trees = BuildTrees(featureToIdx, model);
        pairwiseEffect = CalcMostInteractingFeatures(trees);
    } else {
        pairwiseEffect = CalcMostInteractingFeatures(
            model,
            featureToIdx
        );
    }

    TVector<TInternalFeatureInteraction> result;
    result.reserve(pairwiseEffect.size());
    for (const auto& efffect : pairwiseEffect) {
        result.emplace_back(efffect.Score, features[efffect.Feature1], features[efffect.Feature2]);
    }
    return result;
}

TVector<TFeatureInteraction> CalcFeatureInteraction(
    const TVector<TInternalFeatureInteraction>& internalFeatureInteraction,