Welcome to Dictionary Learning Toolbox’s documentation!
This toolbox solves several Dictionary Learning problems, the basic one being
\[\begin{split}\begin{align}
\min _{D, \mathbf{X}} & \|\mathbf{Y}-\mathbf{D} \mathbf{X}\|_{F}^{2} \\
\text { s.t. } & \left\|\mathbf{x}_{\ell}\right\|_{0} \leq s, \ell=1: N \\
& \left\|\mathbf{d}_{j}\right\|=1, j=1: n
\label{eq-dl}
\end{align}\end{split}\]
where \(\mathbf{Y} \in \mathbb{R}^{m \times N}\) is a given set of \(N\) signals, each of size \(m\), \(\mathbf{D} \in \mathbb{R}^{m \times n}\) is the trained dictionary, \(\mathbf{X} \in \mathbb{R}^{n \times N}\) is the sparse representation matrix (or sparse codes) and \(s\) represents the sparsity level.