Maths for ML / Notation

\mathbf{A}^{\top}

transpose

Linear algebraBeginner

Say it “A transpose”

Flip a matrix over its diagonal: rows become columns. Turns a column vector into a row vector.

Example

\begin{bmatrix}1&2\\3&4\end{bmatrix}^{\top}=\begin{bmatrix}1&3\\2&4\end{bmatrix}

In code

A.T

A.T  # or A.mT for batches

Where you’ll see it in ML

Everywhere: 𝐰ᵀ𝐱, QKᵀ in attention, fixing shape mismatches.

Don’t confuse it with

$\mathbf{A}^{-1}$ matrix inverse The matrix that undoes A: A⁻¹A = I. Only exists for square, non-singular matrices.

Lessons that use it

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