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#backpropagation

4 articles

01 ·Numerical Computing·★ MEMBER·12 min read Build Your Own Autograd — A Mini PyTorch in 100 Lines Start from a single Value class, add operator overloading, topological ordering, and gradient accumulation, then put a neural network on top and train it. Once you have seen the reasons behind each design choice, zero_grad() and retain_graph stop being trivia to memorize. 02 ·Calculus & Optimization·★ MEMBER·11 min read Matrix Calculus from Scratch — Derive the Backward Pass Yourself Where does the transpose in ∂L/∂W = XᵀG actually come from? Matrix calculus is not a formula sheet to memorize — it is one move: rotate dX to the right inside a trace. From denominator layout and shape-checking to the gradients of a linear layer and softmax + cross-entropy, ending with a double-precision gradient check. 03 ·Numerical Computing·FREE·10 min read How Autodiff Actually Works — Unpacking the PyTorch Magic Why does writing loss.backward() hand you derivatives for millions of parameters? We build up computation graphs, the chain rule, and forward vs. reverse mode from zero — then write a working 40-line autograd engine. 04 ·Deep Learning Basics·★ MEMBER·9 min read Backpropagation from Scratch — It Is All Just the Chain Rule Why you can get gradients for ten million parameters for roughly the cost of one forward pass. The chain rule, computational graphs, a two-layer network worked by hand with real numbers, and where vanishing gradients come from — every symbol explained as it appears.