AbstractODEDetector.java
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* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The Hipparchus project licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
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* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.hipparchus.ode.events;
import org.hipparchus.analysis.UnivariateFunction;
import org.hipparchus.analysis.solvers.BracketedUnivariateSolver;
import org.hipparchus.analysis.solvers.BracketingNthOrderBrentSolver;
import org.hipparchus.ode.ODEStateAndDerivative;
/** Base class for #@link {@link ODEEventDetector}.
* @param <T> type of the detector
* @since 3.0
*/
public abstract class AbstractODEDetector<T extends AbstractODEDetector<T>> implements ODEEventDetector {
/** Default maximum checking interval (s). */
public static final double DEFAULT_MAXCHECK = 600;
/** Default convergence threshold (s). */
public static final double DEFAULT_THRESHOLD = 1.e-6;
/** Default maximum number of iterations in the event time search. */
public static final int DEFAULT_MAX_ITER = 100;
/** Max check interval. */
private final AdaptableInterval maxCheck;
/** Maximum number of iterations in the event time search. */
private final int maxIter;
/** Root-finding algorithm to use to detect state events. */
private final BracketedUnivariateSolver<UnivariateFunction> solver;
/** Default handler for event overrides. */
private final ODEEventHandler handler;
/** Propagation direction. */
private boolean forward;
/** Build a new instance.
* @param maxCheck maximum checking interval, must be strictly positive (s)
* @param maxIter maximum number of iterations in the event time search
* @param solver root-finding algorithm to use to detect state events
* @param handler event handler to call at event occurrences
*/
protected AbstractODEDetector(final AdaptableInterval maxCheck, final int maxIter,
final BracketedUnivariateSolver<UnivariateFunction> solver,
final ODEEventHandler handler) {
this.maxCheck = maxCheck;
this.maxIter = maxIter;
this.solver = solver;
this.handler = handler;
this.forward = true;
}
/**
* {@inheritDoc}
*
* <p> This implementation sets the direction of integration and initializes the event
* handler. If a subclass overrides this method it should call {@code
* super.init(s0, t)}.
*/
@Override
public void init(final ODEStateAndDerivative s0, final double t) {
forward = t >= s0.getTime();
getHandler().init(s0, t, this);
}
/** {@inheritDoc} */
@Override
public abstract double g(ODEStateAndDerivative s);
/** {@inheritDoc} */
@Override
public AdaptableInterval getMaxCheckInterval() {
return maxCheck;
}
/** {@inheritDoc} */
@Override
public int getMaxIterationCount() {
return maxIter;
}
/** {@inheritDoc} */
@Override
public BracketedUnivariateSolver<UnivariateFunction> getSolver() {
return solver;
}
/**
* Setup the maximum checking interval.
* <p>
* This will override a maximum checking interval if it has been configured previously.
* </p>
* @param newMaxCheck maximum checking interval
* @return a new detector with updated configuration (the instance is not changed)
*/
public T withMaxCheck(final double newMaxCheck) {
return withMaxCheck(s -> newMaxCheck);
}
/**
* Setup the maximum checking interval.
* <p>
* This will override a maximum checking interval if it has been configured previously.
* </p>
* @param newMaxCheck maximum checking interval
* @return a new detector with updated configuration (the instance is not changed)
* @since 3.0
*/
public T withMaxCheck(final AdaptableInterval newMaxCheck) {
return create(newMaxCheck, getMaxIterationCount(), getSolver(), getHandler());
}
/**
* Setup the maximum number of iterations in the event time search.
* <p>
* This will override a number of iterations if it has been configured previously.
* </p>
* @param newMaxIter maximum number of iterations in the event time search
* @return a new detector with updated configuration (the instance is not changed)
*/
public T withMaxIter(final int newMaxIter) {
return create(getMaxCheckInterval(), newMaxIter, getSolver(), getHandler());
}
/**
* Setup the convergence threshold.
* <p>
* This is equivalent to call {@code withSolver(new BracketingNthOrderBrentSolver(0,
* newThreshold, 0, 5))}, so it will override a solver if one has been configured previously.
* </p>
* @param newThreshold convergence threshold
* @return a new detector with updated configuration (the instance is not changed)
* @see #withSolver(BracketedUnivariateSolver)
*/
public T withThreshold(final double newThreshold) {
return withSolver(new BracketingNthOrderBrentSolver(0, newThreshold, 0, 5));
}
/**
* Setup the root-finding algorithm to use to detect state events.
* <p>
* This will override a solver if it has been configured previously.
* </p>
* @param newSolver root-finding algorithm to use to detect state events
* @return a new detector with updated configuration (the instance is not changed)
* @see #withThreshold(double)
*/
public T withSolver(final BracketedUnivariateSolver<UnivariateFunction> newSolver) {
return create(getMaxCheckInterval(), getMaxIterationCount(), newSolver, getHandler());
}
/**
* Setup the event handler to call at event occurrences.
* <p>
* This will override a handler if it has been configured previously.
* </p>
* @param newHandler event handler to call at event occurrences
* @return a new detector with updated configuration (the instance is not changed)
*/
public T withHandler(final ODEEventHandler newHandler) {
return create(getMaxCheckInterval(), getMaxIterationCount(), getSolver(), newHandler);
}
/** {@inheritDoc} */
@Override
public ODEEventHandler getHandler() {
return handler;
}
/** Build a new instance.
* @param newMaxCheck maximum checking interval
* @param newmaxIter maximum number of iterations in the event time search
* @param newSolver root-finding algorithm to use to detect state events
* @param newHandler event handler to call at event occurrences
* @return a new instance of the appropriate sub-type
*/
protected abstract T create(AdaptableInterval newMaxCheck, int newmaxIter,
BracketedUnivariateSolver<UnivariateFunction> newSolver,
ODEEventHandler newHandler);
/** Check if the current propagation is forward or backward.
* @return true if the current propagation is forward
*/
public boolean isForward() {
return forward;
}
}