1 ## Copyright (C) 2011 Lukas F. Reichlin
3 ## This file is part of LTI Syncope.
5 ## LTI Syncope is free software: you can redistribute it and/or modify
6 ## it under the terms of the GNU General Public License as published by
7 ## the Free Software Foundation, either version 3 of the License, or
8 ## (at your option) any later version.
10 ## LTI Syncope is distributed in the hope that it will be useful,
11 ## but WITHOUT ANY WARRANTY; without even the implied warranty of
12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 ## GNU General Public License for more details.
15 ## You should have received a copy of the GNU General Public License
16 ## along with LTI Syncope. If not, see <http://www.gnu.org/licenses/>.
19 ## @deftypefn {Function File} {@var{bool} =} isminimumphase (@var{sys})
20 ## @deftypefnx {Function File} {@var{bool} =} isminimumphase (@var{sys}, @var{tol})
21 ## Determine whether LTI system is minimum phase.
22 ## The zeros must lie in the left complex half-plane.
23 ## The name minimum-phase refers to the fact that such a system has the
24 ## minimum possible phase lag for the given magnitude response |sys(jw)|.
31 ## Optional tolerance. Default value is 0.
37 ## System is not minimum phase.
39 ## System is minimum phase.
44 ## real (z) < -tol*(1 + abs (z)) continuous-time
45 ## abs (z) < 1 - tol discrete-time
50 ## Author: Lukas Reichlin <lukas.reichlin@gmail.com>
51 ## Created: January 2011
54 function bool = isminimumphase (sys, tol = 0)
63 bool = __is_stable__ (z, ct, tol);