comparison toolboxes/FullBNT-1.0.7/bnt/examples/dynamic/HHMM/mk_hhmm.m @ 0:e9a9cd732c1e tip

first hg version after svn
author wolffd
date Tue, 10 Feb 2015 15:05:51 +0000
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-1:000000000000 0:e9a9cd732c1e
1 function [bnet, Qnodes, Fnodes, Onode] = mk_hhmm(varargin)
2 % MK_HHMM Make a Hierarchical HMM
3 % function [bnet, Qnodes, Fnodes, Onode] = mk_hhmm(...)
4 %
5 % e.g. 3-layer hierarchical HMM where level 1 only connects to level 2
6 % and the parents of the observed node are levels 2 and 3.
7 % (This DBN is the same as Fig 10 in my tech report.)
8 %
9 % Q1 ----------> Q1
10 % | \ ^ |
11 % | v / |
12 % | F2 ------/ |
13 % | ^ ^ \ |
14 % | / | \ |
15 % | / | ||
16 % v | vv
17 % Q2----| --------> Q2
18 % /| \ | ^|
19 % / | v | / |
20 % | | F3 --------/ |
21 % | | ^ \ |
22 % | v / v v
23 % | Q3 -----------> Q3
24 % | |
25 % \ |
26 % v v
27 % O
28 %
29 %
30 % Optional arguments in name/value format [default value in brackets]
31 %
32 % Qsizes - sizes at each level [ none ]
33 % allQ - 1 means level i connects to all Q levels below, 0 means just to i+1 [0]
34 % transprob - transprob{d}(i,k,j) = P(Q(d,t)=j|Q(d,t-1)=i,Q(1:d-1,t)=k) ['leftright']
35 % startprob - startprob{d}(k,j) = P(Q(d,t)=j|Q(1:d-1,t)=k) ['leftstart']
36 % termprob - termprob{d}(k,j) = P(F(d,t)=2|Q(1:d-1,t)=k,Q(d,t)=j) for d>1 ['rightstop']
37 % selfprop - prob of a self transition (termprob default = 1-selfprop) [0.8]
38 % Osize - size of O node
39 % discrete_obs - 1 means O is tabular_CPD, 0 means gaussian_CPD [0]
40 % Oargs - cell array of args to pass to the O CPD [ {} ]
41 % Ops - Q parents of O [Qnodes(end)]
42 % F1 - 1 means level 1 can finish (restart), else there is no F1->Q1 arc [0]
43 % clamp1 - 1 means we clamp the params of the Q nodes in slice 1 (Qt1params) [1]
44 % Note: the Qt1params are startprob, which should be shared with other slices.
45 % However, in the current implementation, the Qt1params will only be estimated
46 % from the initial state of each sequence.
47 %
48 % For d=1, startprob{1}(1,j) is only used in the first slice and
49 % termprob{1} is ignored, since we assume the top level never resets.
50 % Also, transprob{1}(i,j) can be used instead of transprob{1}(i,1,j).
51 %
52 % leftstart means the model always starts in state 1.
53 % rightstop means the model can only finish in its last state (Qsize(d)).
54 % unif means each state is equally like to reach any other
55 % rnd means the transition/starting probs are random (drawn from rand)
56 %
57 % Q1:QD in slice 1 are of type tabular_CPD
58 % Q1:QD in slice 2 are of type hhmmQ_CPD.
59 % F(2:D-1) is of type hhmmF_CPD, FD is of type tabular_CPD.
60
61 args = varargin;
62 nargs = length(args);
63
64 % get sizes of nodes and topology
65 Qsizes = [];
66 Osize = [];
67 allQ = 0;
68 Ops = [];
69 F1 = 0;
70 for i=1:2:nargs
71 switch args{i},
72 case 'Qsizes', Qsizes = args{i+1};
73 case 'Osize', Osize = args{i+1};
74 case 'allQ', allQ = args{i+1};
75 case 'Ops', Ops = args{i+1};
76 case 'F1', F1 = args{i+1};
77 end
78 end
79 if isempty(Qsizes), error('must specify Qsizes'); end
80 if Osize==0, error('must specify Osize'); end
81 D = length(Qsizes);
82 Qnodes = 1:D;
83
84 if isempty(Ops), Ops = Qnodes(end); end
85
86
87 [intra, inter, Qnodes, Fnodes, Onode] = mk_hhmm_topo(D, allQ, Ops, F1);
88 ss = length(intra);
89 names = {};
90
91 if F1
92 Fnodes_ndx = Fnodes;
93 else
94 Fnodes_ndx = [-1 Fnodes]; % Fnodes(1) is a dummy index
95 end
96
97 % set default params
98 discrete_obs = 0;
99 Oargs = {};
100 startprob = cell(1,D);
101 startprob{1} = 'unif';
102 for d=2:D
103 startprob{d} = 'leftstart';
104 end
105 transprob = cell(1,D);
106 transprob{1} = 'unif';
107 for d=2:D
108 transprob{d} = 'leftright';
109 end
110 termprob = cell(1,D);
111 for d=2:D
112 termprob{d} = 'rightstop';
113 end
114 selfprob = 0.8;
115 clamp1 = 1;
116
117 for i=1:2:nargs
118 switch args{i},
119 case 'discrete_obs', discrete_obs = args{i+1};
120 case 'Oargs', Oargs = args{i+1};
121 case 'startprob', startprob = args{i+1};
122 case 'transprob', transprob = args{i+1};
123 case 'termprob', termprob = args{i+1};
124 case 'selfprob', selfprob = args{i+1};
125 case 'clamp1', clamp1 = args{i+1};
126 end
127 end
128
129 ns = zeros(1,ss);
130 ns(Qnodes) = Qsizes;
131 ns(Onode) = Osize;
132 ns(Fnodes) = 2;
133
134 dnodes = [Qnodes Fnodes];
135 if discrete_obs
136 dnodes = [dnodes Onode];
137 end
138 onodes = [Onode];
139
140 bnet = mk_dbn(intra, inter, ns, 'observed', onodes, 'discrete', dnodes, 'names', names);
141 eclass = bnet.equiv_class;
142
143 for d=1:D
144 if d==1
145 Qps = [];
146 elseif allQ
147 Qps = Qnodes(1:d-1);
148 else
149 Qps = Qnodes(d-1);
150 end
151 Qpsz = prod(ns(Qps));
152 Qsz = ns(Qnodes(d));
153 if isstr(startprob{d})
154 switch startprob{d}
155 case 'unif', startprob{d} = mk_stochastic(ones(Qpsz, Qsz));
156 case 'rnd', startprob{d} = mk_stochastic(rand(Qpsz, Qsz));
157 case 'leftstart', startprob{d} = zeros(Qpsz, Qsz); startprob{d}(:,1) = 1;
158 end
159 end
160 if isstr(transprob{d})
161 switch transprob{d}
162 case 'unif', transprob{d} = mk_stochastic(ones(Qsz, Qpsz, Qsz));
163 case 'rnd', transprob{d} = mk_stochastic(rand(Qsz, Qpsz, Qsz));
164 case 'leftright',
165 LR = mk_leftright_transmat(Qsz, selfprob);
166 temp = repmat(reshape(LR, [1 Qsz Qsz]), [Qpsz 1 1]); % transprob(k,i,j)
167 transprob{d} = permute(temp, [2 1 3]); % now transprob(i,k,j)
168 end
169 end
170 if isstr(termprob{d})
171 switch termprob{d}
172 case 'unif', termprob{d} = mk_stochastic(ones(Qpsz, Qsz, 2));
173 case 'rnd', termprob{d} = mk_stochastic(rand(Qpsz, Qsz, 2));
174 case 'rightstop',
175 %termprob(k,i,t) Might terminate if i=Qsz; will not terminate if i<Qsz
176 stopprob = 1-selfprob;
177 termprob{d} = zeros(Qpsz, Qsz, 2);
178 termprob{d}(:,Qsz,2) = stopprob;
179 termprob{d}(:,Qsz,1) = 1-stopprob;
180 termprob{d}(:,1:(Qsz-1),1) = 1;
181 otherwise, error(['unrecognized termprob ' termprob{d}])
182 end
183 elseif d>1 % passed in termprob{d}(k,j)
184 temp = termprob{d};
185 termprob{d} = zeros(Qpsz, Qsz, 2);
186 termprob{d}(:,:,2) = temp;
187 termprob{d}(:,:,1) = ones(Qpsz,Qsz) - temp;
188 end
189 end
190
191
192 % SLICE 1
193
194 for d=1:D
195 bnet.CPD{eclass(Qnodes(d),1)} = tabular_CPD(bnet, Qnodes(d), 'CPT', startprob{d}, 'adjustable', clamp1);
196 end
197
198 if F1
199 d = 1;
200 bnet.CPD{eclass(Fnodes_ndx(d),1)} = hhmmF_CPD(bnet, Fnodes_ndx(d), Qnodes(d), Fnodes_ndx(d+1), ...
201 'termprob', termprob{d});
202 end
203 for d=2:D-1
204 if allQ
205 Qps = Qnodes(1:d-1);
206 else
207 Qps = Qnodes(d-1);
208 end
209 bnet.CPD{eclass(Fnodes_ndx(d),1)} = hhmmF_CPD(bnet, Fnodes_ndx(d), Qnodes(d), Fnodes_ndx(d+1), ...
210 'Qps', Qps, 'termprob', termprob{d});
211 end
212 bnet.CPD{eclass(Fnodes_ndx(D),1)} = tabular_CPD(bnet, Fnodes_ndx(D), 'CPT', termprob{D});
213
214 if discrete_obs
215 bnet.CPD{eclass(Onode,1)} = tabular_CPD(bnet, Onode, Oargs{:});
216 else
217 bnet.CPD{eclass(Onode,1)} = gaussian_CPD(bnet, Onode, Oargs{:});
218 end
219
220 % SLICE 2
221
222 %for d=1:D
223 % bnet.CPD{eclass(Qnodes(d),2)} = hhmmQ_CPD(bnet, Qnodes(d)+ss, Qnodes, d, D, ...
224 % 'startprob', startprob{d}, 'transprob', transprob{d}, ...
225 % 'allQ', allQ);
226 %end
227
228 d = 1;
229 if F1
230 bnet.CPD{eclass(Qnodes(d),2)} = hhmmQ_CPD(bnet, Qnodes(d)+ss, 'Fself', Fnodes_ndx(d), ...
231 'Fbelow', Fnodes_ndx(d+1), ...
232 'startprob', startprob{d}, 'transprob', transprob{d});
233 else
234 bnet.CPD{eclass(Qnodes(d),2)} = hhmmQ_CPD(bnet, Qnodes(d)+ss, ...
235 'Fbelow', Fnodes_ndx(d+1), ...
236 'startprob', startprob{d}, 'transprob', transprob{d});
237 end
238 for d=2:D-1
239 if allQ
240 Qps = Qnodes(1:d-1);
241 else
242 Qps = Qnodes(d-1);
243 end
244 Qps = Qps + ss; % since all in slice 2
245 bnet.CPD{eclass(Qnodes(d),2)} = hhmmQ_CPD(bnet, Qnodes(d)+ss, 'Fself', Fnodes_ndx(d), ...
246 'Fbelow', Fnodes_ndx(d+1), 'Qps', Qps, ...
247 'startprob', startprob{d}, 'transprob', transprob{d});
248 end
249 d = D;
250 if allQ
251 Qps = Qnodes(1:d-1);
252 else
253 Qps = Qnodes(d-1);
254 end
255 Qps = Qps + ss; % since all in slice 2
256 bnet.CPD{eclass(Qnodes(d),2)} = hhmmQ_CPD(bnet, Qnodes(d)+ss, 'Fself', Fnodes_ndx(d), ...
257 'Qps', Qps, ...
258 'startprob', startprob{d}, 'transprob', transprob{d});