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comparison m-toolbox/classes/@pzmodel/fromParfrac.m @ 0:f0afece42f48

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Import.
author Daniele Nicolodi <nicolodi@science.unitn.it>
date Wed, 23 Nov 2011 19:22:13 +0100
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-1:000000000000 0:f0afece42f48
1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2 %
3 % FUNCTION: fromParfrac
4 %
5 % DESCRIPTION: Construct a pzmodel from a partial fractions TF
6 %
7 % CALL: pzm = fromParfrac(a, pl)
8 %
9 % PARAMETER: pl - plist
10 %
11 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
12 function pzm = fromParfrac(pzm, pli)
13
14 VERSION = '$Id: fromParfrac.m,v 1.7 2011/08/15 12:18:38 hewitson Exp $';
15
16
17 % get pzmodel info
18 ii = pzmodel.getInfo('pzmodel', 'From Parfrac');
19
20 % Set the method version string in the minfo object
21 ii.setMversion([VERSION '-->' ii.mversion]);
22
23 % Combine input plist with default values
24 pl = applyDefaults(ii.plists, pli);
25
26 % Set fields
27 pf = find(pl, 'parfrac');
28
29 poles = pf.poles;
30
31 % get numerator
32 [num,den] = residue(pf.res,pf.poles,pf.dir);
33 zeros = roots(num);
34
35 % find dc gain
36 ig = sum(-1*pf.res./poles) + pf.dir;
37
38 % remove conjugate pairs
39 if isempty(poles)
40 ps = [];
41 else
42 ps = {poles(1)};
43 for jj=2:numel(poles)
44 if ~isreal(poles(jj))
45 if~any(conj(poles(jj))==[ps{:}])
46 ps = [ps poles(jj)];
47 end
48 else
49 ps = [ps poles(jj)];
50 end
51 end
52 end
53
54 if isempty(zeros)
55 zs = [];
56 else
57 zs = {zeros(1)};
58 for jj=2:numel(zeros)
59 if ~isreal(zeros(jj))
60 if~any(conj(zeros(jj))==[zs{:}])
61 zs = [zs zeros(jj)];
62 end
63 else
64 zs = [zs zeros(jj)];
65 end
66 end
67 end
68
69 % divide for (-2*pi) only when a real pole or zero is found
70 if ~isempty(ps)
71 numps = cell2mat(ps);
72 numps(imag(numps)==0) = numps(imag(numps)==0)./(2.*sign(numps(imag(numps)==0)).*pi);
73 ps = num2cell(numps);
74 end
75 if ~isempty(zs)
76 numzs = cell2mat(zs);
77 numzs(imag(numzs)==0) = numzs(imag(numzs)==0)./(2.*sign(numzs(imag(numzs)==0)).*pi);
78 zs = num2cell(numzs);
79 end
80
81 pzm = pzmodel(ig, ps, zs);
82
83 % Override some plist values
84 if isempty(pl.find('ounits'))
85 pl.pset('ounits', pf.ounits);
86 end
87
88 if isempty(pl.find('iunits'))
89 pl.pset('iunits', pf.iunits);
90 end
91
92 if isempty(pl.find('name'))
93 pl.pset('name', sprintf('pzmodel(%s)', pf.name));
94 end
95
96 if isempty(pl.find('description'))
97 pl.pset('description', pf.description);
98 end
99
100 % Add history
101 pzm.addHistory(ii, pl, [], pf.hist);
102
103 % Set object properties
104 pzm.setObjectProperties(pl);
105
106 end