“…These include cutting-plane methods that avoid the introduction of the matrix variable P by working directly with the frequency-domain inequality (2) [Par99, KMJ00, KM01, KMJ03, WKH08], interior-point methods based on new barrier functions for the convex set defined by the frequency domain inequalities [KM01, KM03,KM07], and customized implementations of standard interior-point methods for semidefinite programming [HV00, AV02, GHNV03, Hac03, GH03, VBW + 05, LP04,RV06,HWH06,LV07].…”