Spactra radius of a 4×4 matrices

I want to find the Spectra redius of the matrices below but I kept running into problem. syms a b c d e f g F = [0 0 0 a; 0 0 0 b; 0 0 0 c; e f g 0]

syms q r s t u V = [q 0 0 0; r s 0 0; 0 0 t 0; 0 0 0 u]

Vi = inv(V) % calculate inverse of V

K = F*Vi % compute the next generation matrix

[Paul]

What's the difference between this question and the question posted at Spectral radius of 4×4 matrices.?