Parrot's problem
K = parrot(D,r)
matrices
1X2 vector (dimension of the 2,2 part of D
)
Given a matrix D
partitioned as [D11 D12; D21 D22]
where size(D22)=r=[r1,r2]
compute a matrix K
such that
largest singular value of [D11 D12; D21 D22+K]
is minimal (Parrot's problem)