% -*- texinfo -*-
% @deftypefn {Function File} {} ord2 (@var{nfreq}, @var{damp}, @var{gain})
% Creates a continuous 2nd order system with parameters:
%
% @strong{Inputs}
% @table @var
% @item nfreq
% natural frequency [Hz]. (not in rad/s)
% @item damp
% damping coefficient
% @item gain
% dc-gain
% This is steady state value only for damp > 0.
% gain is assumed to be 1.0 if omitted.
% @end table
%
% @strong{Output}
% @table @var
% @item outsys
% system data structure has representation with
% @ifinfo
% @math{w = 2 * pi * nfreq}:
% @end ifinfo
% @iftex
% @tex
% $ w = 2 \pi f $:
% @end tex
% @end iftex
% @example
% @group
% / ...
% | / -2w*damp -w \ / w \ |
% G = | | |, | |, [ 0 gain ], 0 |
% | \ w 0 / \ 0 / |
% \ /
% @end group
% @end example
% @end table
% @strong{See also} @command{jet707} (@acronym{MIMO} example, Boeing 707-321
% aircraft model)
% @end deftypefn