Author: erans Date: Wed Aug 21 02:03:30 2013 New Revision: 1516059 URL: http://svn.apache.org/r1516059 Log: MATH-1014 Container for storing observations, to allow separating the curve fitting algorithms from the data to be fitted.
Added: commons/proper/math/trunk/src/main/java/org/apache/commons/math3/fitting/WeightedObservedPoints.java (with props) commons/proper/math/trunk/src/test/java/org/apache/commons/math3/fitting/WeightedObservedPointsTest.java (with props) Added: commons/proper/math/trunk/src/main/java/org/apache/commons/math3/fitting/WeightedObservedPoints.java URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/main/java/org/apache/commons/math3/fitting/WeightedObservedPoints.java?rev=1516059&view=auto ============================================================================== --- commons/proper/math/trunk/src/main/java/org/apache/commons/math3/fitting/WeightedObservedPoints.java (added) +++ commons/proper/math/trunk/src/main/java/org/apache/commons/math3/fitting/WeightedObservedPoints.java Wed Aug 21 02:03:30 2013 @@ -0,0 +1,113 @@ +/* + * 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.fitting; + +import java.util.List; +import java.util.ArrayList; +import java.io.Serializable; + +/** + * Simple container for weighted observed points used + * in {@link AbstractCurveFitter curve fitting} algorithms. + * + * @version $Id$ + * @since 3.3 + */ +public class WeightedObservedPoints implements Serializable { + /** Serializable version id. */ + private static final long serialVersionUID = 20130813L; + + /** Observed points. */ + private final List<WeightedObservedPoint> observations + = new ArrayList<WeightedObservedPoint>(); + + /** + * Adds a point to the sample. + * Calling this method is equivalent to calling + * {@code add(1.0, x, y)}. + * + * @param x Abscissa of the point. + * @param y Observed value at {@code x}. After fitting we should + * have {@code f(x)} as close as possible to this value. + * + * @see #add(double, double, double) + * @see #add(WeightedObservedPoint) + * @see #getObservations() + */ + public void add(double x, double y) { + add(1d, x, y); + } + + /** + * Adds a point to the sample. + * + * @param weight Weight of the observed point. + * @param x Abscissa of the point. + * @param y Observed value at {@code x}. After fitting we should + * have {@code f(x)} as close as possible to this value. + * + * @see #add(double, double) + * @see #add(WeightedObservedPoint) + * @see #getObservations() + */ + public void add(double weight, double x, double y) { + observations.add(new WeightedObservedPoint(weight, x, y)); + } + + /** + * Adds a point to the sample. + * + * @param observed Observed point to add. + * + * @see #add(double, double) + * @see #add(double, double, double) + * @see #getObservations() + */ + public void add(WeightedObservedPoint observed) { + observations.add(observed); + } + + /** + * Gets a <em>snapshot</em> of the observed points. + * The list of stored points is copied in order to ensure that + * modification of the returned instance does not affect this + * container. + * Conversely, further modification of this container (through + * the {@code add} or {@code clear} methods) will not affect the + * returned list. + * + * @return the observed points, in the order they were added to this + * container. + * + * @see #add(double, double) + * @see #add(double, double, double) + * @see #add(WeightedObservedPoint) + */ + public List<WeightedObservedPoint> toList() { + // The copy is necessary to ensure thread-safety because of the + // "clear" method (which otherwise would be able to empty the + // list of points while it is being used by another thread). + return new ArrayList<WeightedObservedPoint>(observations); + } + + /** + * Removes all observations from this container. + */ + public void clear() { + observations.clear(); + } +} Propchange: commons/proper/math/trunk/src/main/java/org/apache/commons/math3/fitting/WeightedObservedPoints.java ------------------------------------------------------------------------------ svn:eol-style = native Propchange: commons/proper/math/trunk/src/main/java/org/apache/commons/math3/fitting/WeightedObservedPoints.java ------------------------------------------------------------------------------ svn:keywords = Id Revision Added: commons/proper/math/trunk/src/test/java/org/apache/commons/math3/fitting/WeightedObservedPointsTest.java URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/test/java/org/apache/commons/math3/fitting/WeightedObservedPointsTest.java?rev=1516059&view=auto ============================================================================== --- commons/proper/math/trunk/src/test/java/org/apache/commons/math3/fitting/WeightedObservedPointsTest.java (added) +++ commons/proper/math/trunk/src/test/java/org/apache/commons/math3/fitting/WeightedObservedPointsTest.java Wed Aug 21 02:03:30 2013 @@ -0,0 +1,126 @@ +/* + * 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.fitting; + +import java.util.List; +import org.junit.Assert; +import org.junit.Test; +import org.apache.commons.math3.util.Precision; + +/** + * Tests {@link WeightedObservedPoints}. + * + * @version $Id$ + */ +public class WeightedObservedPointsTest { + @Test + public void testAdd1() { + final WeightedObservedPoints store = new WeightedObservedPoints(); + + final double x = 1.2; + final double y = 34.56; + final double w = 0.789; + + store.add(w, x, y); + + Assert.assertTrue(lastElementIsSame(store, new WeightedObservedPoint(w, x, y))); + } + + @Test + public void testAdd2() { + final WeightedObservedPoints store = new WeightedObservedPoints(); + + final double x = 1.2; + final double y = 34.56; + final double w = 0.789; + + store.add(new WeightedObservedPoint(w, x, y)); + + Assert.assertTrue(lastElementIsSame(store, new WeightedObservedPoint(w, x, y))); + } + + @Test + public void testAdd3() { + final WeightedObservedPoints store = new WeightedObservedPoints(); + + final double x = 1.2; + final double y = 34.56; + + store.add(x, y); + + Assert.assertTrue(lastElementIsSame(store, new WeightedObservedPoint(1, x, y))); + } + + @Test + public void testClear() { + final WeightedObservedPoints store = new WeightedObservedPoints(); + + store.add(new WeightedObservedPoint(1, 2, 3)); + store.add(new WeightedObservedPoint(2, -1, -2)); + Assert.assertTrue(store.toList().size() == 2); + + store.clear(); + Assert.assertTrue(store.toList().size() == 0); + } + + // Ensure that an instance returned by "toList()" is independent from + // the original container. + @Test + public void testToListCopy() { + final WeightedObservedPoints store = new WeightedObservedPoints(); + + store.add(new WeightedObservedPoint(1, 2, 3)); + store.add(new WeightedObservedPoint(2, -3, -4)); + + final List<WeightedObservedPoint> list = store.toList(); + Assert.assertTrue(list.size() == 2); + + // Adding an element to "list" has no impact on "store". + list.add(new WeightedObservedPoint(1.2, 3.4, 5.6)); + Assert.assertFalse(list.size() == store.toList().size()); + + // Clearing "store" has no impact on "list". + store.clear(); + Assert.assertFalse(list.size() == 0); + } + + /** + * Checks that the contents of the last element is equal to the + * contents of {@code p}. + * + * @param store Container. + * @param point Observation. + * @return {@code true} if both elements have the same contents. + */ + private boolean lastElementIsSame(WeightedObservedPoints store, + WeightedObservedPoint point) { + final List<WeightedObservedPoint> list = store.toList(); + final WeightedObservedPoint lastPoint = list.get(list.size() - 1); + + if (!Precision.equals(lastPoint.getX(), point.getX())) { + return false; + } + if (!Precision.equals(lastPoint.getY(), point.getY())) { + return false; + } + if (!Precision.equals(lastPoint.getWeight(), point.getWeight())) { + return false; + } + + return true; + } +} Propchange: commons/proper/math/trunk/src/test/java/org/apache/commons/math3/fitting/WeightedObservedPointsTest.java ------------------------------------------------------------------------------ svn:eol-style = native Propchange: commons/proper/math/trunk/src/test/java/org/apache/commons/math3/fitting/WeightedObservedPointsTest.java ------------------------------------------------------------------------------ svn:keywords = Id Revision