🧠 机器学习与神经网络

Decision Tree LiveCART decision tree with Gini impurity splitting; axis-aligned splits emerge level by level… Reinforcement LearningQ-learning agent navigates an 8×8 grid maze. Heatmap shows max Q-values; white arrows show… Self-Organising Map24×24 Kohonen SOM (576 neurons, 3D RGB input). Gaussian neighbourhood update as α and σ… K-Means Clustering — Interactive Machine LearningStep through K-means clustering: watch centroids converge, Voronoi regions update, and… PCA & SVD Visualiser — Principal Component Analysis InteractiveGenerate a 2D dataset, diagonalise covariance matrix into principal components, and watch… PerceptronNewRosenblatt's 1958 algorithm: each misclassified point tilts the weight vector w ← w + η·y·x.… k-Nearest NeighboursNewClassify a point by majority vote among its k closest neighbours. Decision regions update… BackpropagationNewδ pulses flow backward through a small MLP: gradients highlight edges, weights update, and… Random Forest ClassifierNewBagging and random feature selection turn weak decision trees into a robust forest. Compare… t-SNE VisualiserNewt-SNE projects high-dimensional clusters to 2D via gradient descent on KL divergence. Tune… Self-Organising Map (SOM)NewA Kohonen grid folds high-dimensional data into 2D: neuron weights self-organise as σ… Radial Basis Function NetworkNewRadial basis network: N Gaussian bumps of width σ sum into a smooth decision boundary —… K-Means Clustering — Lloyd's AlgorithmNewCluster 2D points with k-means: assign to nearest centroid, move to the mean, repeat. Watch… DBSCAN — Density-Based ClusteringNewDBSCAN grows clusters from dense core points via ε-neighbourhoods and minPts, labelling… Naive Bayes Classifier — Probabilistic DecisionNewClassify 2D points with Gaussian naive Bayes: estimate per-class means and variances, apply… Gradient Descent — 3D Loss Surface & OptimisersNewNavigate a 3D loss landscape (Rosenbrock, Rastrigin, Himmelblau) with SGD, Momentum, RMSprop…