bstap
=====

hankel approximant



Calling Sequence
~~~~~~~~~~~~~~~~


::

    [Q]=bstap(Sl)




Arguments
~~~~~~~~~

:sl linear system ( `syslin` list) assumed continuous-time and anti-
  stable.
: :Q best stable approximation of `Sl` ( `syslin` list).
:



Description
~~~~~~~~~~~

Computes the best approximant `Q` of the linear system `Sl`

where

||T||

is the H-infinity norm of the Hankel operator associated with `Sl`.



See Also
~~~~~~~~


+ `syslin`_ linear system definition


.. _syslin: syslin.html