This course is designed to teach learners how to use a dictionary to look up words and definitions. It will cover topics such as how to use a dictionary to find the correct spelling of a word, how to use a thesaurus to find synonyms and antonyms, and how
Sparse dictionary learning is a representation learning method which aims to find a sparse representation of the input data in the form of a linear combination of basic elements as well as those basic elements themselves. These elements are called atoms, and they compose a dictionary. Atoms in the dictionary are not required to be orthogonal, and they may be an over-complete spanning set. This problem setup also allows the dimensionality of the signals being represented to be higher than any one of the signals being observed. These two properties lead to having seemingly redundant atoms that allow multiple representations of the same signal, but also provide an improvement in sparsity and flexibility of the representation.