home | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (AdamsFieldIntegrator.java)

This example Java source code file (AdamsFieldIntegrator.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

adamsfieldintegrator, adamsnordsieckfieldtransformer, array2drowfieldmatrix, dimensionmismatchexception, fieldexpandableode, fieldodestateandderivative, illegalargumentexception, maxcountexceededexception, nobracketingexception, numberistoosmallexception, override, realfieldelement, string

The AdamsFieldIntegrator.java Java example source code

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF 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
 *
 *      http://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,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.commons.math3.ode.nonstiff;

import org.apache.commons.math3.Field;
import org.apache.commons.math3.RealFieldElement;
import org.apache.commons.math3.exception.DimensionMismatchException;
import org.apache.commons.math3.exception.MaxCountExceededException;
import org.apache.commons.math3.exception.NoBracketingException;
import org.apache.commons.math3.exception.NumberIsTooSmallException;
import org.apache.commons.math3.linear.Array2DRowFieldMatrix;
import org.apache.commons.math3.ode.FieldExpandableODE;
import org.apache.commons.math3.ode.FieldODEState;
import org.apache.commons.math3.ode.FieldODEStateAndDerivative;
import org.apache.commons.math3.ode.MultistepFieldIntegrator;


/** Base class for {@link AdamsBashforthFieldIntegrator Adams-Bashforth} and
 * {@link AdamsMoultonFieldIntegrator Adams-Moulton} integrators.
 * @param <T> the type of the field elements
 * @since 3.6
 */
public abstract class AdamsFieldIntegrator<T extends RealFieldElement extends MultistepFieldIntegrator {

    /** Transformer. */
    private final AdamsNordsieckFieldTransformer<T> transformer;

    /**
     * Build an Adams integrator with the given order and step control parameters.
     * @param field field to which the time and state vector elements belong
     * @param name name of the method
     * @param nSteps number of steps of the method excluding the one being computed
     * @param order order of the method
     * @param minStep minimal step (sign is irrelevant, regardless of
     * integration direction, forward or backward), the last step can
     * be smaller than this
     * @param maxStep maximal step (sign is irrelevant, regardless of
     * integration direction, forward or backward), the last step can
     * be smaller than this
     * @param scalAbsoluteTolerance allowed absolute error
     * @param scalRelativeTolerance allowed relative error
     * @exception NumberIsTooSmallException if order is 1 or less
     */
    public AdamsFieldIntegrator(final Field<T> field, final String name,
                                final int nSteps, final int order,
                                final double minStep, final double maxStep,
                                final double scalAbsoluteTolerance,
                                final double scalRelativeTolerance)
        throws NumberIsTooSmallException {
        super(field, name, nSteps, order, minStep, maxStep,
              scalAbsoluteTolerance, scalRelativeTolerance);
        transformer = AdamsNordsieckFieldTransformer.getInstance(field, nSteps);
    }

    /**
     * Build an Adams integrator with the given order and step control parameters.
     * @param field field to which the time and state vector elements belong
     * @param name name of the method
     * @param nSteps number of steps of the method excluding the one being computed
     * @param order order of the method
     * @param minStep minimal step (sign is irrelevant, regardless of
     * integration direction, forward or backward), the last step can
     * be smaller than this
     * @param maxStep maximal step (sign is irrelevant, regardless of
     * integration direction, forward or backward), the last step can
     * be smaller than this
     * @param vecAbsoluteTolerance allowed absolute error
     * @param vecRelativeTolerance allowed relative error
     * @exception IllegalArgumentException if order is 1 or less
     */
    public AdamsFieldIntegrator(final Field<T> field, final String name,
                                final int nSteps, final int order,
                                final double minStep, final double maxStep,
                                final double[] vecAbsoluteTolerance,
                                final double[] vecRelativeTolerance)
        throws IllegalArgumentException {
        super(field, name, nSteps, order, minStep, maxStep,
              vecAbsoluteTolerance, vecRelativeTolerance);
        transformer = AdamsNordsieckFieldTransformer.getInstance(field, nSteps);
    }

    /** {@inheritDoc} */
    public abstract FieldODEStateAndDerivative<T> integrate(final FieldExpandableODE equations,
                                                            final FieldODEState<T> initialState,
                                                            final T finalTime)
        throws NumberIsTooSmallException, DimensionMismatchException,
               MaxCountExceededException, NoBracketingException;

    /** {@inheritDoc} */
    @Override
    protected Array2DRowFieldMatrix<T> initializeHighOrderDerivatives(final T h, final T[] t,
                                                                      final T[][] y,
                                                                      final T[][] yDot) {
        return transformer.initializeHighOrderDerivatives(h, t, y, yDot);
    }

    /** Update the high order scaled derivatives for Adams integrators (phase 1).
     * <p>The complete update of high order derivatives has a form similar to:
     * <pre>
     * r<sub>n+1 = (s1(n) - s1(n+1)) P-1 u + P-1 A P rn
     * </pre>
     * this method computes the P<sup>-1 A P rn part.

* @param highOrder high order scaled derivatives * (h<sup>2/2 y'', ... hk/k! y(k)) * @return updated high order derivatives * @see #updateHighOrderDerivativesPhase2(RealFieldElement[], RealFieldElement[], Array2DRowFieldMatrix) */ public Array2DRowFieldMatrix<T> updateHighOrderDerivativesPhase1(final Array2DRowFieldMatrix highOrder) { return transformer.updateHighOrderDerivativesPhase1(highOrder); } /** Update the high order scaled derivatives Adams integrators (phase 2). * <p>The complete update of high order derivatives has a form similar to: * <pre> * r<sub>n+1 = (s1(n) - s1(n+1)) P-1 u + P-1 A P rn * </pre> * this method computes the (s<sub>1(n) - s1(n+1)) P-1 u part.

* <p>Phase 1 of the update must already have been performed.

* @param start first order scaled derivatives at step start * @param end first order scaled derivatives at step end * @param highOrder high order scaled derivatives, will be modified * (h<sup>2/2 y'', ... hk/k! y(k)) * @see #updateHighOrderDerivativesPhase1(Array2DRowFieldMatrix) */ public void updateHighOrderDerivativesPhase2(final T[] start, final T[] end, final Array2DRowFieldMatrix<T> highOrder) { transformer.updateHighOrderDerivativesPhase2(start, end, highOrder); } }

Other Java examples (source code examples)

Here is a short list of links related to this Java AdamsFieldIntegrator.java source code file:



my book on functional programming

 

new blog posts

 

Copyright 1998-2019 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.