1 package org.lcsim.recon.tracking.trfcyl;
2
3
4 import org.lcsim.recon.tracking.trfutil.TRFMath;
5 import org.lcsim.recon.tracking.trfutil.Assert;
6
7 import org.lcsim.recon.tracking.trfbase.TrackDerivative;
8 import org.lcsim.recon.tracking.trfbase.TrackVector;
9 import org.lcsim.recon.tracking.trfbase.Propagator;
10 import org.lcsim.recon.tracking.trfbase.PropDirected;
11 import org.lcsim.recon.tracking.trfbase.PropDir;
12 import org.lcsim.recon.tracking.trfbase.PropStat;
13 import org.lcsim.recon.tracking.trfbase.Surface;
14 import org.lcsim.recon.tracking.trfbase.VTrack;
15 import org.lcsim.recon.tracking.trfbase.ETrack;
16
17 /**
18 * PropJoinCyl propagates tracks from a starting surface to a cylinder and
19 * then to the final surface. The radius of the intermediate
20 * cylinder is calculated from two parameters rmin and rfac and
21 * the starting radius r0:
22 * if rfac*r0 < rmin, then r = rmin, otherwise r = rfac*r0.
23 *
24 *@author Norman A. Graf
25 *@version 1.0
26 *
27 */
28
29 public class PropJoinCyl extends PropDirected
30 {
31
32 // static methods
33
34 //
35
36 /**
37 *Return a String representation of the class' type name.
38 *Included for completeness with the C++ version.
39 *
40 * @return A String representation of the class' type name.
41 */
42 public static String typeName()
43 { return "PropJoinCyl";
44 }
45
46 //
47
48 /**
49 *Return a String representation of the class' type name.
50 *Included for completeness with the C++ version.
51 *
52 * @return A String representation of the class' type name.
53 */
54 public static String staticType()
55 { return typeName();
56 }
57
58 // attributes
59
60 // parameters to calculate radius
61 private double _rmin;
62 private double _rfac;
63
64 // The propagators.
65 private Propagator _prop1;
66 private Propagator _prop2;
67
68 //methods
69
70
71 //
72
73 /**
74 *Construct an instance from the two constituent propagators.
75 *
76 * @param rmin The minimum radius.
77 * @param rfac The maximum radius.
78 * @param prop1 The first Propagator.
79 * @param prop2 The second Propagator.
80 */
81 public PropJoinCyl(double rmin, double rfac, Propagator prop1,
82 Propagator prop2)
83 {
84 _rmin = rmin;
85 _rfac = rfac;
86 _prop1 = prop1.newPropagator();
87 _prop2 = prop2.newPropagator();
88 }
89
90 //
91
92 /**
93 *Construct a clone of this instance
94 *
95 * @return A Clone of this instance.
96 */
97 public Propagator newPropagator( )
98 {
99 return new PropJoinCyl(_rmin, _rfac, _prop1.newPropagator(), _prop2.newPropagator());
100 }
101
102 //
103
104 /**
105 *Return a String representation of the class' type name.
106 *Included for completeness with the C++ version.
107 *
108 * @return A String representation of the class' type name.
109 */
110 public String type()
111 { return staticType();
112 }
113
114 //
115
116 /**
117 *Return the minimum radius.
118 *
119 * @return The minimum radius.
120 */
121 public double minRadius()
122 { return _rmin;
123 }
124
125 /**
126 *Return the maximum radius.
127 *
128 * @return The maximum radius.
129 */
130 public double maxRadius()
131 { return _rfac;
132 }
133
134 /**
135 * Return the first Propagator.
136 *
137 * @return The first Propagator.
138 */
139 public Propagator prop1()
140 { return _prop1.newPropagator();
141 }
142
143 /**
144 * Return the second Propagator.
145 *
146 * @return The second Propagator.
147 */
148 public Propagator prop2()
149 { return _prop2.newPropagator();
150 }
151
152 //
153
154 /**
155 *Propagate a track without error in the specified direction.
156 *
157 * @param trv The Vtrack to propagate.
158 * @param srf The surface to which to propagate.
159 * @param dir The direction in which to propagate.
160 * @return The propagation status.
161 */
162 public PropStat vecDirProp(VTrack trv, Surface srf, PropDir dir)
163 {
164 TrackDerivative der = null;
165 return vecDirProp(trv,srf,dir,der);
166 }
167
168 //
169
170 /**
171 *Propagate a track without error in the specified direction
172 * and update the track derivatives at the final surface.
173 *
174 * @param trv The Vtrack to propagate.
175 * @param srf The surface to which to propagate.
176 * @param dir The direction in which to propagate.
177 * @param der the track derivatives to update at the surface srf.
178 * @return The propagation status.
179 */
180 public PropStat vecDirProp(VTrack trv, Surface srf,
181 PropDir dir, TrackDerivative der )
182 {
183 // Construct intermediate derivatives.
184 TrackDerivative tmpder1 = null;
185 TrackDerivative tmpder2 = null;
186 if (der != null)
187 {
188 tmpder1 = new TrackDerivative();
189 tmpder2 = new TrackDerivative();
190 }
191
192 //System.out.println("In PropJoinCyl!");
193 // Propagate from starting surface to cylinder.
194 double r = _rfac*trv.spacePoint().rxy();
195 if ( r < _rmin ) r = _rmin;
196 PropStat pstat = _prop1.vecDirProp(trv, new SurfCylinder(r),
197 PropDir.NEAREST, tmpder1);
198 if ( ! pstat.success() )
199 {
200 return pstat;
201 }
202
203 // Propagate from cylinder to final surface.
204 pstat = _prop2.vecDirProp(trv, srf, dir, tmpder2);
205 if ( ! pstat.success() )
206 {
207 return pstat;
208 }
209
210 // Calculate the overall derivative matrix.
211 if ( der != null )
212 {
213 der = new TrackDerivative( tmpder2.times(tmpder1) );
214 }
215
216 // Return the final status.
217 return pstat;
218
219 }
220 //
221
222 /**
223 *Propagate a track with error in the specified direction.
224 *
225 * @param trv The Etrack to propagate.
226 * @param srf The surface to which to propagate.
227 * @param dir The direction in which to propagate.
228 * @return The propagation status.
229 */
230 public PropStat errDirProp(ETrack trv, Surface srf,
231 PropDir dir)
232 {
233 TrackDerivative der = null;
234 return errDirProp(trv,srf,dir,der);
235 }
236
237 //
238
239 /**
240 *propagate a track with error in the specified direction
241 *
242 * @param trv The Etrack to propagate.
243 * @param srf The surface to which to propagate.
244 * @param dir The direction in which to propagate.
245 * @param der the track derivatives to update at the surface srf.
246 * @return The propagation status.
247 */
248 public PropStat errDirProp(ETrack trv, Surface srf,
249 PropDir dir, TrackDerivative der)
250 {
251 TrackDerivative tmpder1 = null;
252 TrackDerivative tmpder2 = null;
253 if (der != null)
254 {
255 // Construct intermediate derivatives.
256 tmpder1 = new TrackDerivative();
257 tmpder2 = new TrackDerivative();
258 }
259
260 // Propagate from starting surface to cylinder.
261 double r = _rfac*trv.spacePoint().rxy();
262
263 if ( r < _rmin ) r = _rmin;
264 PropStat pstat = _prop1.errDirProp(trv, new SurfCylinder(r),
265 PropDir.NEAREST, tmpder1 );
266 if ( ! pstat.success() )
267 {
268 return pstat;
269 }
270
271 // Propagate from cylinder to final surface.
272 pstat = _prop2.errDirProp(trv, srf, dir, tmpder2);
273 if ( ! pstat.success() )
274 {
275 return pstat;
276 }
277 // Calculate the overall derivative matrix.
278 if ( der != null )
279 {
280 der = new TrackDerivative( tmpder2.times(tmpder1) );
281 }
282 // Return the final status.
283 return pstat;
284
285 }
286
287
288
289 /**
290 *output stream
291 *
292 * @return A String representation of this instance.
293 */
294 public String toString()
295 {
296 StringBuffer sb = new StringBuffer("Propagator using intermediate cylinder.\n");
297 sb.append("rmin = " + _rmin + "; rfac = " + _rfac + "\n");
298 sb.append("First propagator: " + _prop1 + "\n");
299 sb.append("Second propagator: " + _prop2 + "\n");
300 return sb.toString();
301 }
302 }