An estimate of approximation of an analytic function of a matrix by a rational function

M. Ferus, V. G. Kurbatov, I. V. Kurbatova

Let $A$ be a square complex matrix; $z_1$, ..., $z_N\in \mathbb{C}$ be arbitrary (possibly repetitive) points of interpolation; $f$ be an analytic function defined on a neighborhoo…