Two scripts are included here. 1. convsys.m - combines the state space representation of two systems connected in series. [Ao,Bo,Co,Do]=convsys(A1,B1,C1,D1,A2,B2,C2,D2) This algorithm gives the convolution of two state space representations | A1 B1 | | A2 B2 | u ==> | | ==> | | ==> y | C1 D1 | | C2 D2 | The algorithm also accepts state space objects as inputs and gives out a state space object as output. 2. sysfeedbk.m [Ao,Bo,Co,Do]=convsys(A1,B1,C1,D1,A2,B2,C2,D2) Gives the closed loop state space representation for two systems connected with negative feedback in the following manner. | A1 B1 | u ==> | | ==> y + o | C1 D1 | | - | | | | A2 B2 | | |= | |= | | C2 D2 | The zip file also contains checkcompatibility.m , which checks the compatibility of matrix dimensions in the system and cleanss.m which can be used to clean a state space representation.