parrot Parrot's problem

## Syntax

    K = parrot(D,r)

## Arguments

D,K

  matrices

r

  1X2 vector (dimension of the 2,2 part of `D`)

## Description

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)

## See also

- h_inf_st