Maths for ML / Notation

\operatorname{rank}(\mathbf{A})

rank

Linear algebraIntermediate

Say it “rank of A”

How many truly independent directions a matrix has.

Example

\operatorname{rank}(\mathbf{u}\mathbf{v}^{\top}) = 1

In code

np.linalg.matrix_rank(A)

torch.linalg.matrix_rank(A)

Where you’ll see it in ML

LoRA: fine-tune with a low-rank update instead of a full matrix.

Don’t confuse it with

$\ll$ much less than Left side is smaller by a large factor (think orders of magnitude).

Lessons that use it

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