Web-Based Control System Analysis and Design
## Connect

#### DESCRIPTION:

This function will construct a state-space model from unconnected block-diagonal models.
Different from other interconnection functions, this function allows
the user to define
the external inputs and external outputs for the connected system. So additional
information should be submitted in this function.

It's important to understand that the indices for both inputs and outputs of two systems
Sys1 and Sys2 should be assigned
continuously. For example, Sys1 has n inputs and m outputs, Sys2 has p inputs and q
outputs, then the indices for Sys1 inputs should be 1 to n, and the
indices for Sys2 inputs should be n+1 to n+p; and the indices for Sys1 outputs should be
1 to m, the indices for Sys2 outputs should be m+1 to m+q.

In order to obtain the connected model Sys, the user needs to fill out the
subsystem interconnection form which specifies the external inputs and external outputs
of Sys and the connection information of two susbsystems.
The first line of the form specifies the external inputs of Sys.
The second line of the form specifies the external outputs of Sys.
The third line of the form specifies the output indices of Sys1 which are
connected to the input of Sys2. The forth line of the form specifies the
input indices of Sys2 which are connected to the output of Sys1.

The following diagram shows how the arrays should be filled out for a certain connection
of two subsystems.

Example.