Raymond | dee0849 | 2015-04-02 10:43:13 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Licensed to the Apache Software Foundation (ASF) under one or more |
| 3 | * contributor license agreements. See the NOTICE file distributed with |
| 4 | * this work for additional information regarding copyright ownership. |
| 5 | * The ASF licenses this file to You under the Apache License, Version 2.0 |
| 6 | * (the "License"); you may not use this file except in compliance with |
| 7 | * the License. You may obtain a copy of the License at |
| 8 | * |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | * |
| 11 | * Unless required by applicable law or agreed to in writing, software |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | * See the License for the specific language governing permissions and |
| 15 | * limitations under the License. |
| 16 | */ |
| 17 | |
| 18 | package org.apache.commons.math.ode.events; |
| 19 | |
| 20 | import java.util.ArrayList; |
| 21 | import java.util.Collection; |
| 22 | import java.util.Collections; |
| 23 | import java.util.List; |
| 24 | |
| 25 | import org.apache.commons.math.ConvergenceException; |
| 26 | import org.apache.commons.math.ode.DerivativeException; |
| 27 | import org.apache.commons.math.ode.IntegratorException; |
| 28 | import org.apache.commons.math.ode.sampling.StepInterpolator; |
| 29 | |
| 30 | /** This class manages several {@link EventHandler event handlers} during integration. |
| 31 | * |
| 32 | * @see EventHandler |
| 33 | * @see EventState |
| 34 | * @version $Revision: 1073158 $ $Date: 2011-02-21 22:46:52 +0100 (lun. 21 févr. 2011) $ |
| 35 | * @since 1.2 |
| 36 | * @deprecated as of 2.2, this class is not used anymore |
| 37 | */ |
| 38 | @Deprecated |
| 39 | public class CombinedEventsManager { |
| 40 | |
| 41 | /** Events states. */ |
| 42 | private final List<EventState> states; |
| 43 | |
| 44 | /** First active event. */ |
| 45 | private EventState first; |
| 46 | |
| 47 | /** Initialization indicator. */ |
| 48 | private boolean initialized; |
| 49 | |
| 50 | /** Simple constructor. |
| 51 | * Create an empty manager |
| 52 | */ |
| 53 | public CombinedEventsManager() { |
| 54 | states = new ArrayList<EventState>(); |
| 55 | first = null; |
| 56 | initialized = false; |
| 57 | } |
| 58 | |
| 59 | /** Add an events handler. |
| 60 | * @param handler event handler |
| 61 | * @param maxCheckInterval maximal time interval between events |
| 62 | * checks (this interval prevents missing sign changes in |
| 63 | * case the integration steps becomes very large) |
| 64 | * @param convergence convergence threshold in the event time search |
| 65 | * @param maxIterationCount upper limit of the iteration count in |
| 66 | * the event time search |
| 67 | * @see #getEventsHandlers() |
| 68 | * @see #clearEventsHandlers() |
| 69 | */ |
| 70 | public void addEventHandler(final EventHandler handler, final double maxCheckInterval, |
| 71 | final double convergence, final int maxIterationCount) { |
| 72 | states.add(new EventState(handler, maxCheckInterval, |
| 73 | convergence, maxIterationCount)); |
| 74 | } |
| 75 | |
| 76 | /** Get all the events handlers that have been added to the manager. |
| 77 | * @return an unmodifiable collection of the added event handlers |
| 78 | * @see #addEventHandler(EventHandler, double, double, int) |
| 79 | * @see #clearEventsHandlers() |
| 80 | * @see #getEventsStates() |
| 81 | */ |
| 82 | public Collection<EventHandler> getEventsHandlers() { |
| 83 | final List<EventHandler> list = new ArrayList<EventHandler>(); |
| 84 | for (EventState state : states) { |
| 85 | list.add(state.getEventHandler()); |
| 86 | } |
| 87 | return Collections.unmodifiableCollection(list); |
| 88 | } |
| 89 | |
| 90 | /** Remove all the events handlers that have been added to the manager. |
| 91 | * @see #addEventHandler(EventHandler, double, double, int) |
| 92 | * @see #getEventsHandlers() |
| 93 | */ |
| 94 | public void clearEventsHandlers() { |
| 95 | states.clear(); |
| 96 | } |
| 97 | |
| 98 | /** Get all the events state wrapping the handlers that have been added to the manager. |
| 99 | * @return a collection of the events states |
| 100 | * @see #getEventsHandlers() |
| 101 | */ |
| 102 | public Collection<EventState> getEventsStates() { |
| 103 | return states; |
| 104 | } |
| 105 | |
| 106 | /** Check if the manager does not manage any event handlers. |
| 107 | * @return true if manager is empty |
| 108 | */ |
| 109 | public boolean isEmpty() { |
| 110 | return states.isEmpty(); |
| 111 | } |
| 112 | |
| 113 | /** Evaluate the impact of the proposed step on all managed |
| 114 | * event handlers. |
| 115 | * @param interpolator step interpolator for the proposed step |
| 116 | * @return true if at least one event handler triggers an event |
| 117 | * before the end of the proposed step (this implies the step should |
| 118 | * be rejected) |
| 119 | * @exception DerivativeException if the interpolator fails to |
| 120 | * compute the function somewhere within the step |
| 121 | * @exception IntegratorException if an event cannot be located |
| 122 | */ |
| 123 | public boolean evaluateStep(final StepInterpolator interpolator) |
| 124 | throws DerivativeException, IntegratorException { |
| 125 | |
| 126 | try { |
| 127 | |
| 128 | first = null; |
| 129 | if (states.isEmpty()) { |
| 130 | // there is nothing to do, return now to avoid setting the |
| 131 | // interpolator time (and hence avoid unneeded calls to the |
| 132 | // user function due to interpolator finalization) |
| 133 | return false; |
| 134 | } |
| 135 | |
| 136 | if (! initialized) { |
| 137 | |
| 138 | // initialize the events states |
| 139 | for (EventState state : states) { |
| 140 | state.reinitializeBegin(interpolator); |
| 141 | } |
| 142 | |
| 143 | initialized = true; |
| 144 | |
| 145 | } |
| 146 | |
| 147 | // check events occurrence |
| 148 | for (EventState state : states) { |
| 149 | |
| 150 | if (state.evaluateStep(interpolator)) { |
| 151 | if (first == null) { |
| 152 | first = state; |
| 153 | } else { |
| 154 | if (interpolator.isForward()) { |
| 155 | if (state.getEventTime() < first.getEventTime()) { |
| 156 | first = state; |
| 157 | } |
| 158 | } else { |
| 159 | if (state.getEventTime() > first.getEventTime()) { |
| 160 | first = state; |
| 161 | } |
| 162 | } |
| 163 | } |
| 164 | } |
| 165 | |
| 166 | } |
| 167 | |
| 168 | return first != null; |
| 169 | |
| 170 | } catch (EventException se) { |
| 171 | final Throwable cause = se.getCause(); |
| 172 | if ((cause != null) && (cause instanceof DerivativeException)) { |
| 173 | throw (DerivativeException) cause; |
| 174 | } |
| 175 | throw new IntegratorException(se); |
| 176 | } catch (ConvergenceException ce) { |
| 177 | throw new IntegratorException(ce); |
| 178 | } |
| 179 | |
| 180 | } |
| 181 | |
| 182 | /** Get the occurrence time of the first event triggered in the |
| 183 | * last evaluated step. |
| 184 | * @return occurrence time of the first event triggered in the last |
| 185 | * evaluated step, or </code>Double.NaN</code> if no event is |
| 186 | * triggered |
| 187 | */ |
| 188 | public double getEventTime() { |
| 189 | return (first == null) ? Double.NaN : first.getEventTime(); |
| 190 | } |
| 191 | |
| 192 | /** Inform the event handlers that the step has been accepted |
| 193 | * by the integrator. |
| 194 | * @param t value of the independent <i>time</i> variable at the |
| 195 | * end of the step |
| 196 | * @param y array containing the current value of the state vector |
| 197 | * at the end of the step |
| 198 | * @exception IntegratorException if the value of one of the |
| 199 | * events states cannot be evaluated |
| 200 | */ |
| 201 | public void stepAccepted(final double t, final double[] y) |
| 202 | throws IntegratorException { |
| 203 | try { |
| 204 | for (EventState state : states) { |
| 205 | state.stepAccepted(t, y); |
| 206 | } |
| 207 | } catch (EventException se) { |
| 208 | throw new IntegratorException(se); |
| 209 | } |
| 210 | } |
| 211 | |
| 212 | /** Check if the integration should be stopped at the end of the |
| 213 | * current step. |
| 214 | * @return true if the integration should be stopped |
| 215 | */ |
| 216 | public boolean stop() { |
| 217 | for (EventState state : states) { |
| 218 | if (state.stop()) { |
| 219 | return true; |
| 220 | } |
| 221 | } |
| 222 | return false; |
| 223 | } |
| 224 | |
| 225 | /** Let the event handlers reset the state if they want. |
| 226 | * @param t value of the independent <i>time</i> variable at the |
| 227 | * beginning of the next step |
| 228 | * @param y array were to put the desired state vector at the beginning |
| 229 | * of the next step |
| 230 | * @return true if the integrator should reset the derivatives too |
| 231 | * @exception IntegratorException if one of the events states |
| 232 | * that should reset the state fails to do it |
| 233 | */ |
| 234 | public boolean reset(final double t, final double[] y) |
| 235 | throws IntegratorException { |
| 236 | try { |
| 237 | boolean resetDerivatives = false; |
| 238 | for (EventState state : states) { |
| 239 | if (state.reset(t, y)) { |
| 240 | resetDerivatives = true; |
| 241 | } |
| 242 | } |
| 243 | return resetDerivatives; |
| 244 | } catch (EventException se) { |
| 245 | throw new IntegratorException(se); |
| 246 | } |
| 247 | } |
| 248 | |
| 249 | } |