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Platform/tests/TestAdaBoost.cpp

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// ***************************************************************
// SPDX-FileCopyrightText: Copyright 2024 Ricardo Montañana Gómez
// SPDX-FileType: SOURCE
// SPDX-License-Identifier: MIT
// ***************************************************************
#include <catch2/catch_test_macros.hpp>
#include <catch2/catch_approx.hpp>
#include <catch2/matchers/catch_matchers_string.hpp>
#include <catch2/matchers/catch_matchers_vector.hpp>
#include <torch/torch.h>
#include <memory>
#include <stdexcept>
#include "experimental_clfs/AdaBoost.h"
#include "experimental_clfs/DecisionTree.h"
#include "common/TensorUtils.hpp"
#include "TestUtils.h"
using namespace bayesnet;
using namespace Catch::Matchers;
static const bool DEBUG = false;
TEST_CASE("AdaBoost Construction", "[AdaBoost]")
{
SECTION("Default constructor")
{
REQUIRE_NOTHROW(AdaBoost());
}
SECTION("Constructor with parameters")
{
REQUIRE_NOTHROW(AdaBoost(100, 2));
}
SECTION("Constructor parameter access")
{
AdaBoost ada(75, 3);
REQUIRE(ada.getNEstimators() == 75);
REQUIRE(ada.getBaseMaxDepth() == 3);
}
}
TEST_CASE("AdaBoost Hyperparameter Setting", "[AdaBoost]")
{
AdaBoost ada;
SECTION("Set individual hyperparameters")
{
REQUIRE_NOTHROW(ada.setNEstimators(100));
REQUIRE_NOTHROW(ada.setBaseMaxDepth(5));
REQUIRE(ada.getNEstimators() == 100);
REQUIRE(ada.getBaseMaxDepth() == 5);
}
SECTION("Set hyperparameters via JSON")
{
nlohmann::json params;
params["n_estimators"] = 80;
params["base_max_depth"] = 4;
REQUIRE_NOTHROW(ada.setHyperparameters(params));
}
SECTION("Invalid hyperparameters should throw")
{
nlohmann::json params;
// Negative n_estimators
params["n_estimators"] = -1;
REQUIRE_THROWS_AS(ada.setHyperparameters(params), std::invalid_argument);
// Zero n_estimators
params["n_estimators"] = 0;
REQUIRE_THROWS_AS(ada.setHyperparameters(params), std::invalid_argument);
// Negative base_max_depth
params["n_estimators"] = 50;
params["base_max_depth"] = -1;
REQUIRE_THROWS_AS(ada.setHyperparameters(params), std::invalid_argument);
// Zero base_max_depth
params["base_max_depth"] = 0;
REQUIRE_THROWS_AS(ada.setHyperparameters(params), std::invalid_argument);
}
}
TEST_CASE("AdaBoost Basic Functionality", "[AdaBoost]")
{
// Create a simple dataset
int n_samples = 20;
int n_features = 2;
std::vector<std::vector<int>> X(n_features, std::vector<int>(n_samples));
std::vector<int> y(n_samples);
// Simple pattern: class depends on first feature
for (int i = 0; i < n_samples; i++) {
X[0][i] = i < 10 ? 0 : 1;
X[1][i] = i % 2;
y[i] = X[0][i]; // Class equals first feature
}
std::vector<std::string> features = { "f1", "f2" };
std::string className = "class";
std::map<std::string, std::vector<int>> states;
states["f1"] = { 0, 1 };
states["f2"] = { 0, 1 };
states["class"] = { 0, 1 };
SECTION("Training with vector interface")
{
AdaBoost ada(10, 3); // 10 estimators, max_depth = 3
REQUIRE_NOTHROW(ada.fit(X, y, features, className, states, Smoothing_t::NONE));
// Check that we have the expected number of models
auto weights = ada.getEstimatorWeights();
REQUIRE(weights.size() <= 10); // Should be <= n_estimators
REQUIRE(weights.size() > 0); // Should have at least one model
// Check training errors
auto errors = ada.getTrainingErrors();
REQUIRE(errors.size() == weights.size());
// All training errors should be less than 0.5 for this simple dataset
for (double error : errors) {
REQUIRE(error < 0.5);
REQUIRE(error >= 0.0);
}
}
SECTION("Prediction before fitting")
{
AdaBoost ada;
REQUIRE_THROWS_WITH(ada.predict(X),
ContainsSubstring("not been fitted"));
REQUIRE_THROWS_WITH(ada.predict_proba(X),
ContainsSubstring("not been fitted"));
}
SECTION("Prediction with vector interface")
{
AdaBoost ada(10, 3);
ada.setDebug(DEBUG); // Enable debug to investigate
ada.fit(X, y, features, className, states, Smoothing_t::NONE);
auto predictions = ada.predict(X);
REQUIRE(predictions.size() == static_cast<size_t>(n_samples));
// Check accuracy
int correct = 0;
for (size_t i = 0; i < predictions.size(); i++) {
if (predictions[i] == y[i]) correct++;
}
double accuracy = static_cast<double>(correct) / n_samples;
REQUIRE(accuracy > 0.99); // Should achieve good accuracy on this simple dataset
auto accuracy_computed = ada.score(X, y);
REQUIRE(accuracy_computed == Catch::Approx(accuracy).epsilon(1e-6));
}
SECTION("Probability predictions with vector interface")
{
AdaBoost ada(10, 3);
ada.setDebug(DEBUG); // ENABLE DEBUG HERE TOO
ada.fit(X, y, features, className, states, Smoothing_t::NONE);
auto proba = ada.predict_proba(X);
REQUIRE(proba.size() == static_cast<size_t>(n_samples));
REQUIRE(proba[0].size() == 2); // Two classes
// Check probabilities sum to 1 and are valid
auto predictions = ada.predict(X);
int correct = 0;
for (size_t i = 0; i < proba.size(); i++) {
auto p = proba[i];
auto pred = predictions[i];
REQUIRE(p.size() == 2);
REQUIRE(p[0] >= 0.0);
REQUIRE(p[1] >= 0.0);
double sum = p[0] + p[1];
REQUIRE(sum == Catch::Approx(1.0).epsilon(1e-6));
// compute the predicted class based on probabilities
auto predicted_class = (p[0] > p[1]) ? 0 : 1;
// compute accuracy based on predictions
if (predicted_class == y[i]) {
correct++;
}
INFO("Probability test - Sample " << i << ": pred=" << pred << ", probs=[" << p[0] << "," << p[1] << "], expected_from_probs=" << predicted_class);
// Handle ties
if (std::abs(p[0] - p[1]) < 1e-10) {
INFO("Tie detected in probabilities");
// Either prediction is valid in case of tie
} else {
// Check that predict_proba matches the expected predict value
REQUIRE(pred == predicted_class);
}
}
double accuracy = static_cast<double>(correct) / n_samples;
REQUIRE(accuracy > 0.99); // Should achieve good accuracy on this simple dataset
}
}
TEST_CASE("AdaBoost Tensor Interface", "[AdaBoost]")
{
auto raw = RawDatasets("iris", true);
SECTION("Training with tensor format")
{
AdaBoost ada(20, 3);
INFO("Dataset shape: " << raw.dataset.sizes());
INFO("Features: " << raw.featurest.size());
INFO("Samples: " << raw.nSamples);
// AdaBoost expects dataset in format: features x samples, with labels as last row
REQUIRE_NOTHROW(ada.fit(raw.dataset, raw.featurest, raw.classNamet, raw.statest, Smoothing_t::NONE));
// Test prediction with tensor
auto predictions = ada.predict(raw.Xt);
REQUIRE(predictions.size(0) == raw.yt.size(0));
// Calculate accuracy
auto correct = torch::sum(predictions == raw.yt).item<int>();
double accuracy = static_cast<double>(correct) / raw.yt.size(0);
auto accuracy_computed = ada.score(raw.Xt, raw.yt);
REQUIRE(accuracy_computed == Catch::Approx(accuracy).epsilon(1e-6));
REQUIRE(accuracy > 0.97); // Should achieve good accuracy on Iris
// Test probability predictions with tensor
auto proba = ada.predict_proba(raw.Xt);
REQUIRE(proba.size(0) == raw.yt.size(0));
REQUIRE(proba.size(1) == 3); // Three classes in Iris
// Check probabilities sum to 1
auto prob_sums = torch::sum(proba, 1);
for (int i = 0; i < prob_sums.size(0); i++) {
REQUIRE(prob_sums[i].item<double>() == Catch::Approx(1.0).epsilon(1e-6));
}
}
}
TEST_CASE("AdaBoost SAMME Algorithm Validation", "[AdaBoost]")
{
auto raw = RawDatasets("iris", true);
SECTION("Prediction consistency with probabilities")
{
AdaBoost ada(15, 3);
ada.setDebug(DEBUG); // Enable debug for ALL instances
ada.fit(raw.dataset, raw.featurest, raw.classNamet, raw.statest, Smoothing_t::NONE);
auto predictions = ada.predict(raw.Xt);
auto probabilities = ada.predict_proba(raw.Xt);
REQUIRE(predictions.size(0) == probabilities.size(0));
REQUIRE(probabilities.size(1) == 3); // Three classes in Iris
// For each sample, predicted class should correspond to highest probability
for (int i = 0; i < predictions.size(0); i++) {
int predicted_class = predictions[i].item<int>();
auto probs = probabilities[i];
// Find class with highest probability
auto max_prob_idx = torch::argmax(probs).item<int>();
// Predicted class should match class with highest probability
REQUIRE(predicted_class == max_prob_idx);
// Probabilities should sum to 1
double sum_probs = torch::sum(probs).item<double>();
REQUIRE(sum_probs == Catch::Approx(1.0).epsilon(1e-6));
// All probabilities should be non-negative
for (int j = 0; j < 3; j++) {
REQUIRE(probs[j].item<double>() >= 0.0);
REQUIRE(probs[j].item<double>() <= 1.0);
}
}
}
SECTION("Weighted voting verification")
{
// Simple dataset where we can verify the weighted voting
std::vector<std::vector<int>> X = { {0,0,1,1}, {0,1,0,1} };
std::vector<int> y = { 0, 1, 1, 0 };
std::vector<std::string> features = { "f1", "f2" };
std::string className = "class";
std::map<std::string, std::vector<int>> states;
states["f1"] = { 0, 1 };
states["f2"] = { 0, 1 };
states["class"] = { 0, 1 };
AdaBoost ada(5, 2);
ada.setDebug(DEBUG); // Enable debug for detailed logging
ada.fit(X, y, features, className, states, Smoothing_t::NONE);
INFO("=== Final test verification ===");
auto predictions = ada.predict(X);
auto probabilities = ada.predict_proba(X);
auto alphas = ada.getEstimatorWeights();
INFO("Training info:");
for (size_t i = 0; i < alphas.size(); i++) {
INFO(" Model " << i << ": alpha=" << alphas[i]);
}
REQUIRE(predictions.size() == 4);
REQUIRE(probabilities.size() == 4);
REQUIRE(probabilities[0].size() == 2); // Two classes
REQUIRE(alphas.size() > 0);
// Verify that estimator weights are reasonable
for (double alpha : alphas) {
REQUIRE(alpha >= 0.0); // Alphas should be non-negative
}
// Verify prediction-probability consistency with detailed logging
for (size_t i = 0; i < predictions.size(); i++) {
int pred = predictions[i];
auto probs = probabilities[i];
INFO("Final check - Sample " << i << ": predicted=" << pred << ", probabilities=[" << probs[0] << "," << probs[1] << "]");
// Handle the case where probabilities are exactly equal (tie)
if (std::abs(probs[0] - probs[1]) < 1e-10) {
INFO("Tie detected in probabilities - either prediction is valid");
REQUIRE((pred == 0 || pred == 1));
} else {
// Normal case - prediction should match max probability
int expected_pred = (probs[0] > probs[1]) ? 0 : 1;
INFO("Expected prediction based on probs: " << expected_pred);
REQUIRE(pred == expected_pred);
}
REQUIRE(probs[0] + probs[1] == Catch::Approx(1.0).epsilon(1e-6));
}
}
SECTION("Empty models edge case")
{
AdaBoost ada(1, 1);
ada.setDebug(DEBUG); // Enable debug for ALL instances
// Try to predict before fitting
std::vector<std::vector<int>> X = { {0}, {1} };
REQUIRE_THROWS_WITH(ada.predict(X), ContainsSubstring("not been fitted"));
REQUIRE_THROWS_WITH(ada.predict_proba(X), ContainsSubstring("not been fitted"));
}
}
TEST_CASE("AdaBoost Debug - Simple Dataset Analysis", "[AdaBoost][debug]")
{
// Create the exact same simple dataset that was failing
int n_samples = 20;
int n_features = 2;
std::vector<std::vector<int>> X(n_features, std::vector<int>(n_samples));
std::vector<int> y(n_samples);
// Simple pattern: class depends on first feature
for (int i = 0; i < n_samples; i++) {
X[0][i] = i < 10 ? 0 : 1;
X[1][i] = i % 2;
y[i] = X[0][i]; // Class equals first feature
}
std::vector<std::string> features = { "f1", "f2" };
std::string className = "class";
std::map<std::string, std::vector<int>> states;
states["f1"] = { 0, 1 };
states["f2"] = { 0, 1 };
states["class"] = { 0, 1 };
SECTION("Debug training process")
{
AdaBoost ada(5, 3); // Few estimators for debugging
ada.setDebug(DEBUG);
// This should work perfectly on this simple dataset
REQUIRE_NOTHROW(ada.fit(X, y, features, className, states, Smoothing_t::NONE));
// Get training details
auto weights = ada.getEstimatorWeights();
auto errors = ada.getTrainingErrors();
INFO("Number of models trained: " << weights.size());
INFO("Training errors: ");
for (size_t i = 0; i < errors.size(); i++) {
INFO(" Model " << i << ": error=" << errors[i] << ", weight=" << weights[i]);
}
// Should have at least one model
REQUIRE(weights.size() > 0);
REQUIRE(errors.size() == weights.size());
// All training errors should be reasonable for this simple dataset
for (double error : errors) {
REQUIRE(error >= 0.0);
REQUIRE(error < 0.5); // Should be better than random
}
// Test predictions
auto predictions = ada.predict(X);
REQUIRE(predictions.size() == static_cast<size_t>(n_samples));
// Calculate accuracy
int correct = 0;
for (size_t i = 0; i < predictions.size(); i++) {
if (predictions[i] == y[i]) correct++;
INFO("Sample " << i << ": predicted=" << predictions[i] << ", actual=" << y[i]);
}
double accuracy = static_cast<double>(correct) / n_samples;
INFO("Accuracy: " << accuracy);
// Should achieve high accuracy on this perfectly separable dataset
REQUIRE(accuracy >= 0.9); // Lower threshold for debugging
// Test probability predictions
auto proba = ada.predict_proba(X);
REQUIRE(proba.size() == static_cast<size_t>(n_samples));
// Verify probabilities are valid
for (size_t i = 0; i < proba.size(); i++) {
auto p = proba[i];
REQUIRE(p.size() == 2);
REQUIRE(p[0] >= 0.0);
REQUIRE(p[1] >= 0.0);
double sum = p[0] + p[1];
REQUIRE(sum == Catch::Approx(1.0).epsilon(1e-6));
// Predicted class should match highest probability
int pred_class = predictions[i];
// Handle ties
if (std::abs(p[0] - p[1]) < 1e-10) {
INFO("Tie detected - probabilities are equal");
REQUIRE((pred_class == 0 || pred_class == 1));
} else {
REQUIRE(pred_class == (p[0] > p[1] ? 0 : 1));
}
}
}
SECTION("Compare with single DecisionTree")
{
// Test that AdaBoost performs at least as well as a single tree
DecisionTree single_tree(3, 2, 1);
single_tree.fit(X, y, features, className, states, Smoothing_t::NONE);
auto tree_predictions = single_tree.predict(X);
int tree_correct = 0;
for (size_t i = 0; i < tree_predictions.size(); i++) {
if (tree_predictions[i] == y[i]) tree_correct++;
}
double tree_accuracy = static_cast<double>(tree_correct) / n_samples;
AdaBoost ada(5, 3);
ada.setDebug(DEBUG);
ada.fit(X, y, features, className, states, Smoothing_t::NONE);
auto ada_predictions = ada.predict(X);
int ada_correct = 0;
for (size_t i = 0; i < ada_predictions.size(); i++) {
if (ada_predictions[i] == y[i]) ada_correct++;
}
double ada_accuracy = static_cast<double>(ada_correct) / n_samples;
INFO("DecisionTree accuracy: " << tree_accuracy);
INFO("AdaBoost accuracy: " << ada_accuracy);
// AdaBoost should perform at least as well as single tree
// (allowing small tolerance for numerical differences)
REQUIRE(ada_accuracy >= tree_accuracy - 0.1);
}
}
TEST_CASE("AdaBoost Predict-Proba Consistency Fix", "[AdaBoost][consistency]")
{
// Simple binary classification dataset
std::vector<std::vector<int>> X = { {0,0,1,1}, {0,1,0,1} };
std::vector<int> y = { 0, 0, 1, 1 };
std::vector<std::string> features = { "f1", "f2" };
std::string className = "class";
std::map<std::string, std::vector<int>> states;
states["f1"] = { 0, 1 };
states["f2"] = { 0, 1 };
states["class"] = { 0, 1 };
SECTION("Binary classification consistency")
{
AdaBoost ada(3, 2);
ada.setDebug(DEBUG); // Enable debug output
ada.fit(X, y, features, className, states, Smoothing_t::NONE);
INFO("=== Debugging predict vs predict_proba consistency ===");
// Get training info
auto alphas = ada.getEstimatorWeights();
auto errors = ada.getTrainingErrors();
INFO("Training completed:");
INFO(" Number of models: " << alphas.size());
for (size_t i = 0; i < alphas.size(); i++) {
INFO(" Model " << i << ": alpha=" << alphas[i] << ", error=" << errors[i]);
}
auto predictions = ada.predict(X);
auto probabilities = ada.predict_proba(X);
// Verify consistency for each sample
for (size_t i = 0; i < predictions.size(); i++) {
int predicted_class = predictions[i];
auto probs = probabilities[i];
INFO("Sample " << i << ":");
INFO(" Features: [" << X[0][i] << ", " << X[1][i] << "]");
INFO(" True class: " << y[i]);
INFO(" Predicted class: " << predicted_class);
INFO(" Probabilities: [" << probs[0] << ", " << probs[1] << "]");
// The predicted class should be the one with highest probability
int max_prob_class = (probs[0] > probs[1]) ? 0 : 1;
INFO(" Max prob class: " << max_prob_class);
// Handle tie case (when probabilities are equal)
if (std::abs(probs[0] - probs[1]) < 1e-10) {
INFO(" Tie detected - probabilities are equal");
// In case of tie, either prediction is valid
REQUIRE((predicted_class == 0 || predicted_class == 1));
} else {
REQUIRE(predicted_class == max_prob_class);
}
// Probabilities should sum to 1
double sum_probs = probs[0] + probs[1];
REQUIRE(sum_probs == Catch::Approx(1.0).epsilon(1e-6));
// All probabilities should be valid
REQUIRE(probs[0] >= 0.0);
REQUIRE(probs[1] >= 0.0);
REQUIRE(probs[0] <= 1.0);
REQUIRE(probs[1] <= 1.0);
}
}
}