Optimize ComputeCPT method with a approx. 30% reducing time

CHANGELOG.md

@@ -7,14 +7,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-## [1.1.1] - 2025-05-08
+## [1.1.1] - 2025-05-20
 
 ### Internal
 
 - Fix the vcpkg configuration in building the library.
 - Fix the sample app to use the vcpkg configuration.
 - Add predict_proba method to all Ld classifiers.
-- Optimize the computeCPT method in the Node class with libtorch vectorized operations and remove the for loop.
+- Refactor the computeCPT method in the Node class with libtorch vectorized operations.
+- Refactor the sample to use local discretization models.
 
 ## [1.1.0] - 2025-04-27
 

Makefile

@@ -111,12 +111,13 @@ release: ## Build a Release version of the project
 	@echo ">>> Done";
 
 fname = "tests/data/iris.arff"
+model = "TANLd"
 sample: ## Build sample
 	@echo ">>> Building Sample...";
 	@if [ -d ./sample/build ]; then rm -rf ./sample/build; fi
 	@cd sample && cmake -B build -S . -D CMAKE_BUILD_TYPE=Release -DCMAKE_TOOLCHAIN_FILE=${VCPKG_ROOT}/scripts/buildsystems/vcpkg.cmake && \
 	cmake --build build -t bayesnet_sample
-	sample/build/bayesnet_sample $(fname)
+	sample/build/bayesnet_sample $(fname) $(model)
 	@echo ">>> Done";
 
 fname = "tests/data/iris.arff"

bayesnet/classifiers/Proposal.cc

@@ -23,6 +23,7 @@ namespace bayesnet {
             throw std::invalid_argument("y must be an integer tensor");
         }
     }
+    // Fit method for single classifier
     map<std::string, std::vector<int>> Proposal::localDiscretizationProposal(const map<std::string, std::vector<int>>& oldStates, Network& model)
     {
         // order of local discretization is important. no good 0, 1, 2...

bayesnet/classifiers/SPODELd.cc

@@ -45,7 +45,6 @@ namespace bayesnet {
     }
     torch::Tensor SPODELd::predict_proba(torch::Tensor& X)
     {
-        std::cout << "Debug: SPODELd::predict_proba" << std::endl;
         auto Xt = prepareX(X);
         return SPODE::predict_proba(Xt);
     }

bayesnet/network/Node.cc

@@ -5,6 +5,7 @@
 // ***************************************************************
 
 #include "Node.h"
+#include <iterator>
 
 namespace bayesnet {
 
@@ -94,43 +95,34 @@ namespace bayesnet {
     {
         dimensions.clear();
         dimensions.reserve(parents.size() + 1);
-        // Get dimensions of the CPT
         dimensions.push_back(numStates);
         for (const auto& parent : parents) {
             dimensions.push_back(parent->getNumStates());
         }
-        // Create a tensor initialized with smoothing
         cpTable = torch::full(dimensions, smoothing, torch::kDouble);
-        // Create a map for quick feature index lookup
-        std::unordered_map<std::string, int> cachedFeatureIndexMap;
-        bool featureIndexMapReady = false;
-        // Build featureIndexMap if not ready
-        if (!featureIndexMapReady) {
-            cachedFeatureIndexMap.clear();
-            for (size_t i = 0; i < features.size(); ++i) {
-                cachedFeatureIndexMap[features[i]] = i;
-            }
-            featureIndexMapReady = true;
+
+        // Build feature index map
+        std::unordered_map<std::string, int> featureIndexMap;
+        for (size_t i = 0; i < features.size(); ++i) {
+            featureIndexMap[features[i]] = i;
         }
-        const auto& featureIndexMap = cachedFeatureIndexMap;
+
         // Gather indices for node and parents
         std::vector<int64_t> all_indices;
-        all_indices.push_back(featureIndexMap.at(name));
+        all_indices.push_back(featureIndexMap[name]);
         for (const auto& parent : parents) {
-            all_indices.push_back(featureIndexMap.at(parent->getName()));
+            all_indices.push_back(featureIndexMap[parent->getName()]);
         }
+
         // Extract relevant columns: shape (num_features, num_samples)
         auto indices_tensor = dataset.index_select(0, torch::tensor(all_indices, torch::kLong));
-        // Transpose to (num_samples, num_features)
-        indices_tensor = indices_tensor.transpose(0, 1).to(torch::kLong);
-        // Flatten CPT for easier indexing
-        auto flat_cpt = cpTable.flatten();
-        // Compute strides for flattening multi-dim indices
+        indices_tensor = indices_tensor.transpose(0, 1).to(torch::kLong); // (num_samples, num_features)
+
+        // Manual flattening of indices
         std::vector<int64_t> strides(all_indices.size(), 1);
         for (int i = strides.size() - 2; i >= 0; --i) {
             strides[i] = strides[i + 1] * cpTable.size(i + 1);
         }
-        // Compute flat indices for each sample
         auto indices_tensor_cpu = indices_tensor.cpu();
         auto indices_accessor = indices_tensor_cpu.accessor<int64_t, 2>();
         std::vector<int64_t> flat_indices(indices_tensor.size(0));
@@ -141,13 +133,15 @@ namespace bayesnet {
             }
             flat_indices[i] = idx;
         }
+
         // Accumulate weights into flat CPT
+        auto flat_cpt = cpTable.flatten();
         auto flat_indices_tensor = torch::from_blob(flat_indices.data(), { (int64_t)flat_indices.size() }, torch::kLong).clone();
         flat_cpt.index_add_(0, flat_indices_tensor, weights.cpu());
         cpTable = flat_cpt.view(cpTable.sizes());
+
         // Normalize the counts (dividing each row by the sum of the row)
         cpTable /= cpTable.sum(0, true);
-        return;
     }
     double Node::getFactorValue(std::map<std::string, int>& evidence)
     {

sample/sample.cc

@@ -69,8 +69,8 @@ std::tuple<torch::Tensor, torch::Tensor, std::vector<std::string>, std::string>
 
 int main(int argc, char* argv[])
 {
-    if (argc < 2) {
-        std::cerr << "Usage: " << argv[0] << " <file_name>" << std::endl;
+    if (argc < 3) {
+        std::cerr << "Usage: " << argv[0] << " <arff_file_name> <model>" << std::endl;
         return 1;
     }
     std::string file_name = argv[1];
@@ -79,6 +79,11 @@ int main(int argc, char* argv[])
     };
     if (models.find(model_name) == models.end()) {
         std::cerr << "Model not found: " << model_name << std::endl;
+        std::cerr << "Available models: ";
+        for (const auto& model : models) {
+            std::cerr << model.first << " ";
+        }
+        std::cerr << std::endl;
         return 1;
     }
     auto clf = models[model_name];