Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works

matrix

A rectangular table of numbers, $m$ rows by $n$ columns; entry $W_{ij}$ sits in row $i$ , column $j$ .

Examples

Stacking neuron 1's weights $(0.5, 0.2)$ and neuron 2's weights $(-1, 0.4)$ as two rows gives a $(2,2)$ matrix $W$ .