sm2ss system matrix to state-space

## Syntax

    Sl = sm2ss(Sm)

## Arguments

Sm

  polynomial matrix (pencil system matrix)

Sl

  linear system (`syslin` list)

## Description

Utility function: converts the system matrix:

    Sm = [-sI + A   B;
         [    C     D]

to linear system in state-space representation (`syslin`) list.

## See also

- systmat
- ss2des