Matlab has the ability to store and manipulate sparse matrices, which greatly increases its usefulness for realistic problems. Creating a sparse matrix can be rather difficult, but manipulating them is easy, since the same operators apply to both sparse and dense matrices. In particular, the backslash operator works with sparse matrices, so sparse systems can be solved in the same fashion as dense systems. Some of the built-in functions apply to sparse matrices, but others do not (for example, eig can be used on sparse symmetric matrix, but not on a sparse nonsymmetric matrix).