1. All blocks in a Simulink model are linearized individually. The default algorithm uses preprogrammed analytic block Jacobians for most blocks which should result in more accurate linearization than numerical perturbation of block inputs and states.
2. With each block linearized, the linearization code then computes how each block is connected to the other blocks in the Simulink model.
3. With the linearization of each block completed, the linearization code then transforms the sample rate of each block to a single sample rate specified by the user.
4. The state-space model that is eventually returned from the linearization code is then computed using the block-by-block linearizations and their interconnection information.
Note that all the information is stored in the sparse matrices to reduce the memory requirements for the algorithm.
