1 ## Copyright (C) 2009, 2010, 2012 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 ## Return frequency response H and frequency vector w.
20 ## If w is empty, it will be calculated by __frequency_vector__.
22 ## Author: Lukas Reichlin <lukas.reichlin@gmail.com>
23 ## Created: November 2009
26 function [H, w] = __frequency_response__ (sys, w = [], mimoflag = 0, resptype = 0, wbounds = "std", cellflag = false)
29 if(! isa (sys, "lti"))
30 error ("frequency_response: first argument sys must be an LTI system");
33 if (! mimoflag && ! issiso (sys))
34 error ("frequency_response: require SISO system");
39 warning ("frequency_response: second argument w is ignored");
42 H = __freqresp__ (sys, [], resptype, cellflag);
43 elseif (isempty (w)) # find interesting frequency range w if not specified
44 w = __frequency_vector__ (sys, wbounds);
45 H = __freqresp__ (sys, w, resptype, cellflag);
46 elseif (iscell (w) && numel (w) == 2 && issample (w{1}) && issample (w{2}))
47 w = __frequency_vector__ (sys, wbounds, w{1}, w{2});
48 H = __freqresp__ (sys, w, resptype, cellflag);
49 elseif (! is_real_vector (w))
50 error ("frequency_response: second argument w must be a vector of frequencies");
52 H = __freqresp__ (sys, w, resptype, cellflag);