Graph, Planar graphs; geometric and topological aspects of graph theory, Positive semidefinite minimum rank, Discrete Mathematics and Combinatorics, Hermitian, skew-Hermitian, and related matrices, Inertia set, cover, Numerical Analysis, Vector spaces, linear dependence, rank, lineability, outerplanar, symmetric, Algebra and Number Theory, Universally optimal matrix, Graphs and linear algebra (matrices, eigenvalues, etc.), Minimum rank, positive semidefinite minimum rank, graph, inertia set, universally optimal matrix, Symmetric, minimum rank, Geometry and Topology, Outerplanar, Cover