001/**
002 * Copyright (c) 2011, The University of Southampton and the individual contributors.
003 * All rights reserved.
004 *
005 * Redistribution and use in source and binary forms, with or without modification,
006 * are permitted provided that the following conditions are met:
007 *
008 *   *  Redistributions of source code must retain the above copyright notice,
009 *      this list of conditions and the following disclaimer.
010 *
011 *   *  Redistributions in binary form must reproduce the above copyright notice,
012 *      this list of conditions and the following disclaimer in the documentation
013 *      and/or other materials provided with the distribution.
014 *
015 *   *  Neither the name of the University of Southampton nor the names of its
016 *      contributors may be used to endorse or promote products derived from this
017 *      software without specific prior written permission.
018 *
019 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
020 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
021 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
022 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
023 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
024 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
025 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
026 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
027 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
028 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
029 */
030package org.openimaj.ml.timeseries.processor.interpolation;
031
032import org.openimaj.ml.timeseries.TimeSeries;
033import org.openimaj.ml.timeseries.processor.TimeSeriesProcessor;
034import org.openimaj.ml.timeseries.processor.interpolation.util.TimeSpanUtils;
035import org.openimaj.ml.timeseries.series.DoubleTimeSeries;
036
037/**
038 * Interpolate values of a time series. Useful for filling in missing values and homogonising 
039 * disperate sets of {@link TimeSeries} data
040 * 
041 * @author Sina Samangooei (ss@ecs.soton.ac.uk)
042 *
043 */
044public abstract class TimeSeriesInterpolation implements TimeSeriesProcessor<double[],Double,DoubleTimeSeries> {
045        
046        private long[] times;
047        
048        /**
049         * The processor's times are set to default, i.e. from min to max time in steps of 1 long
050         */
051        public TimeSeriesInterpolation() {
052                times = null;
053        }
054        
055        
056        /**
057         * @param begin 
058         * @param end 
059         * @param delta 
060         */
061        public TimeSeriesInterpolation(long begin, long end, long delta) {
062                this.times = TimeSpanUtils.getTime(begin,end, delta);
063        }
064        
065        /**
066         * @param begin 
067         * @param steps 
068         * @param delta 
069         */
070        public TimeSeriesInterpolation(long begin, int steps, long delta) {
071                this.times = TimeSpanUtils.getTime(begin,steps, delta);
072        }
073        
074        /**
075         * @param begin the start of the new time series
076         * @param end the end of the new time series
077         * @param steps the steps between (begin = 0, end = 10, 6 steps will give 0, 2, 4, 6, 8, 10
078         */
079        public TimeSeriesInterpolation(long begin, long end, int steps) {
080                this.times = TimeSpanUtils.getTime(begin,end, steps);
081        }
082        
083        /**
084         * @param times the times used by the processor
085         */
086        public TimeSeriesInterpolation(long[] times) {
087                this.times = times;
088        }
089        
090        /**
091         * Uses {@link #interpolate(DoubleTimeSeries, long[])} to return an interpolation of the construction
092         * {@link TimeSeries} between the times at the required interval
093         * @param series 
094         * @param begin time to start
095         * @param end time to end
096         * @param delta the delta between time steps
097         * @return {@link DoubleTimeSeries} instance interpolated from the construction {@link TimeSeries} instance
098         */
099        public DoubleTimeSeries interpolate(DoubleTimeSeries series, long begin, long end, long delta){
100                long[] times = TimeSpanUtils.getTime(begin,end,delta);
101                return interpolate(series,times);
102        }
103        /**
104         * Uses {@link #interpolate(DoubleTimeSeries, long[])} to return an interpolation of the construction
105         * {@link TimeSeries} from begin, for a number of steps with a given delta between steps
106         * @param series 
107         * @param begin
108         * @param steps
109         * @param delta
110         * @return {@link DoubleTimeSeries} instance interpolated from the construction {@link TimeSeries} instance
111         */
112        public DoubleTimeSeries interpolate(DoubleTimeSeries series, long begin, int steps, long delta){
113                long[] times = TimeSpanUtils.getTime(begin,steps,delta);
114                return interpolate(series,times);
115        }
116        /**
117         * Uses {@link #interpolate(DoubleTimeSeries,long[])} to return an interpolation of the construction
118         * {@link TimeSeries} from begin, until end with a delta which means that there are
119         * splits time instances
120         * @param series 
121         * @param begin 
122         * @param end
123         * @param splits
124         * @return {@link DoubleTimeSeries} instance interpolated from the construction {@link TimeSeries} instance
125         */
126        public DoubleTimeSeries interpolate(DoubleTimeSeries series, long begin, long end, int splits){
127                long[] times = TimeSpanUtils.getTime(begin,end,splits);
128                return interpolate(series,times);
129        }
130        
131        /**
132         * @param series
133         * @return a new {@link DoubleTimeSeries} interpolated with times provided in the constructor
134         */
135        public DoubleTimeSeries interpolate(DoubleTimeSeries series){
136                return interpolate(series,this.times);
137        }
138        /**
139         * @param series 
140         * @param times might be null, therefore some "defualt" time step should be used
141         * @return {@link DoubleTimeSeries} instance interpolated from the construction {@link TimeSeries} instance
142         */
143        public abstract DoubleTimeSeries interpolate(DoubleTimeSeries series, long[] times);
144        
145        @Override
146        public void process(DoubleTimeSeries ts) {
147                ts.internalAssign(this.interpolate(ts,times));
148        }
149}