A method for the inverse numerical range problem
Christos Chorianopoulos, Panayiotis Psarrakos, Frank Uhlig · Electronic Journal of Linear Algebra · 2010
For a given complex square matrix A, we develop, implement and test a fast geometric algorithm to find a unit vector that generates a given point in the complex plane if this point lies inside the numerical range of A, and if not, the method determines that the given point lies outside the numerical range.