The dimensions of sets of matrices of various types, with specified eigenvalue multiplicities, are determined. The dimensions of the sets of matrices with given Jordan form and with given singular value multiplicities are also found. Each corresponding codimension is the number of conditions which a matrix of the given type must satisfy in order to have the specified multiplicities. © 2008 Elsevier Inc. All rights reserved.
Keller, J. B. (2008). Multiple eigenvalues. Linear Algebra and Its Applications, 429(8–9), 2209–2220. https://doi.org/10.1016/j.laa.2008.06.022