Function HasNonZeroApproxForZeroWeightLeaf

catboost/libs/fstr/util.cpp:112–126

}

bool HasNonZeroApproxForZeroWeightLeaf(const TFullModel& model) {
    for (size_t leafIdx = 0; leafIdx < model.ModelTrees->GetModelTreeData()->GetLeafWeights().size(); ++leafIdx) {
        size_t approxDimension = model.GetDimensionsCount();
        if (model.ModelTrees->GetModelTreeData()->GetLeafWeights()[leafIdx] == 0) {
            double leafSumApprox = 0;
            for (size_t approxIdx = 0; approxIdx < approxDimension; ++approxIdx) {
                leafSumApprox += abs(model.ModelTrees->GetModelTreeData()->GetLeafValues()[leafIdx * approxDimension + approxIdx]);
            }
            if (leafSumApprox >= 1e-9) {
                return true;
            }
        }
    }
    return false;
}

bool NeedDatasetForLeavesWeights(const TFullModel& model, bool fstrOnTrainPool) {
    const auto leafWeightsOfModels = model.ModelTrees->GetModelTreeData()->GetLeafWeights();