1 package org.lcsim.recon.tracking.gtrbase;
2 // McTrack
3
4 import java.util.Set;
5 import java.util.SortedSet;
6 import java.util.TreeSet;
7 import java.util.Iterator;
8 import org.lcsim.recon.tracking.trfbase.Surface;
9
10 /**
11 * This class describes a propagated Monte Carlo track.
12 * It is made up of a set of McTrackStates along the trajectory
13 * of the track.
14 *<p>
15 * We use a SortedSet to guarantee ordering in s.
16 *<p>
17 * The first state is the start of the trajectory (production
18 * or entering detector volume) and the last is the end of the
19 * trajectory (decay or volume exit).
20 *<p>
21 * The VTrack's represent the changing state of the track.
22 *<p>
23 * Users may fetch the entire set of states or may request the
24 * state at a specified surface.
25 *
26 *@author Norman A. Graf
27 *@version 1.0
28 *
29 */
30 public class McTrack
31 {
32 // attributes
33
34 private static McTrackState BadState = new McTrackState();
35
36 // Version number
37 private int _version;
38
39 // List of states.
40 private SortedSet _states;
41
42 // MC Particle Id
43 // Id of the MC particle which created the states of this track
44 int _mctrackid;
45
46 // PDG particle type
47 int _pdgid;
48
49 // Particle Parentage
50 // Packed word containing information about particles heritage
51 int _parentword;
52
53 // methods
54
55 // Return the index for the first matching state.
56 // Return -1 if there is no match.
57 private int find( Surface srf)
58 {
59 int count = 0;
60 for ( Iterator ista=_states.iterator(); ista.hasNext(); )
61 if ( ((McTrackState)ista.next()).track().surface().pureEqual(srf) ) return count++;
62 return -1;
63
64 }
65 // methods
66
67 /**
68 *Construct a default instance.
69 * Leaves object in invalid state.
70 *
71 */
72 public McTrack()
73 {
74 }
75
76 /**
77 *Construct a replica of the McTrack (copy constructor).
78 *
79 * @param mct The McTrack to replicate.
80 */
81 public McTrack(McTrack mct)
82 {
83 _states = new TreeSet();
84 for(Iterator it = mct._states.iterator(); it.hasNext(); )
85 {
86 _states.add(it.next());
87 }
88 _mctrackid = mct._mctrackid;
89 _parentword = mct._parentword;
90 _pdgid = mct._pdgid;
91 }
92
93 /**
94 * Construct n instance from a list of states, the MC Track ID, and a
95 * packed parent word (see gtrbase/McParent).
96 * Size must be nonzero and all states must be valid or
97 * assertion is thrown and all states are discarded.
98 *
99 * @param states A list of track states.
100 * @param mcid The MC track ID.
101 * @param parentword A packed parent word.
102 * @param pdgid The pdgid associated with this track.
103 */
104 public McTrack( Set states, int mcid, int parentword, int pdgid)
105 {
106 _states = new TreeSet();
107 for(Iterator it = states.iterator(); it.hasNext(); )
108 {
109 _states.add(it.next());
110 }
111 _mctrackid = mcid;
112 _parentword = parentword;
113 _pdgid = pdgid;
114 // Check that all states are valid.
115 int ok_count = 0;
116 for ( Iterator ista=_states.iterator(); ista.hasNext(); )
117 {
118 if ( ! ((McTrackState)ista.next()).isValid() ) break;
119 ++ok_count;
120 }
121 if( ok_count != _states.size() ) throw new IllegalArgumentException("McTrackStates not valid!");
122 if ( ok_count != _states.size() )
123 _states.clear();
124
125 }
126
127 /**
128 *Test track validity.
129 *
130 * @return true if this track has one or more states.
131 */
132 public boolean isValid()
133 {
134 if(_states == null) return false;
135 return _states.size()!=0;
136 }
137
138 /**
139 *Return the list of states.
140 *
141 * @return The list of states comprising this track.
142 */
143 public Set states()
144 {
145 TreeSet states = new TreeSet();
146 for(Iterator it = _states.iterator(); it.hasNext(); )
147 {
148 states.add(it.next());
149 }
150 return states;
151 }
152
153 /**
154 *Return whether a surface can be matched.
155 *
156 * @param srf The surface to check.
157 * @return true whether this track contains a state at the surface srf.
158 */
159 public boolean hasSurface( Surface srf)
160 {
161 return find(srf) != -1;
162 }
163
164 /**
165 *Return the state for a particular surface.
166 *The first match is returned.
167 * Surface bounds are not required to match.
168 * A reference to an invalid state is returned if the surface
169 * cannot be matched.
170 *
171 * @param srf The surface for which the state is requested.
172 * @return The McTrackState at the surface srf.
173 */
174 public McTrackState state( Surface srf)
175 {
176 for ( Iterator ista=_states.iterator(); ista.hasNext(); )
177 {
178 McTrackState tmp = (McTrackState)ista.next();
179 if ( tmp.track().surface().pureEqual(srf) ) return new McTrackState(tmp);
180 }
181 return BadState;
182 }
183
184 /**
185 *Add an McTrackState to this track.
186 *
187 * @param state The McTrackState to add.
188 */
189 public void addState(McTrackState state)
190 {
191 if(_states == null) _states = new TreeSet();
192 if(_states.contains(state)) throw new IllegalArgumentException("McTrack already contains this state!");
193 _states.add(new McTrackState(state));
194 }
195
196 /**
197 *Return the MC Id for the Track creating this track's states.
198 *
199 * @return The MC track ID.
200 */
201 public int mcTrackId()
202 {
203 return _mctrackid;
204 }
205
206 /**
207 *Set the MC Id for the Track creating this track's states.
208 *
209 * @param mctrackid The MC track ID.
210 */
211 public void setMcTrackId( int mctrackid)
212 {
213 _mctrackid = mctrackid;
214 }
215
216
217 /**
218 *Return the PDG particle Id for the Track creating this track's states.
219 *
220 * @return The MC track pdg ID.
221 */
222 public int pdgId()
223 {
224 return _pdgid;
225 }
226
227 /**
228 *Set the PDG particle Id for the Track creating this track's states
229 *
230 * @param pdgid The MC track pdg ID.
231 */
232 public void setPdgId( int pdgid)
233 {
234 _pdgid = pdgid;
235 }
236
237
238 /**
239 *Return the parentage of this particle.
240 *
241 * @return The MCParent for this track's MC track.
242 */
243 public McParent parent()
244 {
245 return new McParent(_parentword);
246 }
247
248 /**
249 *Set the MC parentage of this particle.
250 *
251 * @param parent The MCParent for this track's MC track.
252 */
253 public void setParent(McParent parent)
254 {
255 _parentword = parent.parentWord();
256 }
257
258 /**
259 *Set the MC parentage of this particle
260 *
261 * @param parentword The packed MC parentage.
262 */
263 public void setParent(int parentword)
264 {
265 _parentword = parentword;
266 }
267
268 /**
269 *output stream
270 *
271 * @return A String representation of this instance.
272 */
273 public String toString()
274 {
275 StringBuffer sb;
276 if(isValid())
277 {
278 sb = new StringBuffer("McTrack of type ");
279 sb.append(pdgId() + " and track ID " + mcTrackId()+"\n");
280 sb.append( "with " +_states.size() + " MC track states\n\n");
281 for(Iterator it = _states.iterator(); it.hasNext(); )
282 {
283 sb.append(it.next());
284 }
285 }
286 else
287 {
288 sb = new StringBuffer("Invalid McTrack");
289 }
290 return sb.toString();
291 }
292
293 /**
294 *Equality
295 *
296 * @param mct The McTrack to test.
297 * @return true if equal.
298 */
299 public boolean equals(McTrack mct)
300 {
301 return _states.equals(mct._states);
302 }
303
304
305 /**
306 *Test inequality.
307 *
308 * @param mct The McTrack to test.
309 * @return true if not equal.
310 */
311 public boolean notEquals(McTrack mct)
312 {
313 return !equals(mct);
314 }
315
316 }