Pseudo-inverse

When talking about pseudo-inverse of a matrix $$A$$, we usually refer to a matrix denoted as $$A^\dagger$$ and is a specific generalized inverse of $$A$$. The form of this specific matrix depends on the type of matrix.

If $$A$$ is skinny and full rank, we generally refer to: $$A^\dagger = (A^T A)^{-1} A_T$$

TBC

The pseudo-inverse is also referred to as the Penrose-Moore inverse.