code: /*******************************************************************************
   * Copyright (c) 2014 Attila Kovacs <attila[AT]sigmyne.com>.
   * All rights reserved. 
   * 
   * This file is part of crush.
   * 
   *     crush is free software: you can redistribute it and/or modify
   *     it under the terms of the GNU General Public License as published by
   *     the Free Software Foundation, either version 3 of the License, or
   *     (at your option) any later version.
   * 
   *     crush is distributed in the hope that it will be useful,
   *     but WITHOUT ANY WARRANTY; without even the implied warranty of
   *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *     GNU General Public License for more details.
   * 
   *     You should have received a copy of the GNU General Public License
   *     along with crush.  If not, see <http://www.gnu.org/licenses/>.
   * 
   * Contributors:
   *     Attila Kovacs <attila[AT]sigmyne.com> - initial API and implementation
   ******************************************************************************/
  
  package crush.telescope.jcmt;
  
  
  import java.io.IOException;
  import java.util.Collections;
  import java.util.Hashtable;
  
  import crush.CRUSH;
  import jnum.Configurator;
  import jnum.Unit;
  import jnum.Util;
  import jnum.data.DataPoint;
  import jnum.data.LocalAverage;
  import jnum.data.Locality;
  import jnum.data.LocalizedData;
  import jnum.io.LineParser;
  import jnum.text.SmartTokenizer;
  
  
  public class JCMTTauTable  extends LocalAverage<JCMTTauTable.Entry> {
  	/**
  	 * 
  	 */
  	private static final long serialVersionUID = -2346424548165913964L;
  	private static Hashtable<String, JCMTTauTable> tables = new Hashtable<>();
  	public String fileName;
  	public double timeWindow = 0.5 * Unit.hour;
  	
  	public static JCMTTauTable get(int iMJD, String fileName) throws IOException {
  		JCMTTauTable table = tables.get(fileName);
  		if(table == null) {
  			table = new JCMTTauTable(iMJD, fileName);
  			tables.put(fileName, table);
  		}
  		return table;
  	}
  	
  	private JCMTTauTable(int iMJD, String fileName) throws IOException {
  		read(iMJD, fileName);	
  	}
  	
  	public void setOptions(Configurator options) {
  		if(options.containsKey("window")) timeWindow = options.option("window").getDouble() * Unit.hour;
  	}
  	
  	protected void read(final int iMJD, String fileName) throws IOException {
  	    new LineParser() {
              @Override
              protected boolean parse(String line) throws Exception {
                  SmartTokenizer tokens = new SmartTokenizer(line);
                  Entry skydip = new Entry();
                  skydip.timeStamp = new TimeStamp(iMJD, tokens.nextToken());
                  skydip.tau.setValue(tokens.nextDouble());
                  //tokens.nextToken();
                  skydip.tau.setRMS(0.001);
                  add(skydip);
                  return true;
              }
  	    }.read(fileName);
  		
  		CRUSH.info(this, "[Loading tau data] " + size() + " values parsed.");
  		
  		Collections.sort(this);
  		
  		this.fileName = fileName;
  	}	
  		
  	
  	public double getTau(double MJD) {	
  		Entry mean = getLocalAverage(new TimeStamp(MJD));
  			
  		if(mean.tau.weight() == 0.0) {
  			CRUSH.info(this, "... No skydip data was found in specified time window.");
  			
  			if(timeWindow < 6.0 * Unit.hour) {
  				CRUSH.info(this, "... expanding tau lookup window to 6 hours.");
  				timeWindow = 6.0 * Unit.hour;
  				mean = getLocalAverage(new TimeStamp(MJD));
  			}
  			else {
  				CRUSH.warning(this, "Tau is unknown.");
  				return 0.0;
  			}
  		}
  		
  		CRUSH.values(this, "Local average tau = " + Util.f3.format(mean.tau.value()) + " (from " + mean.measurements + " measurements)");
  		return mean.tau.value();
  	}
  	
  	class TimeStamp extends Locality {
  		double MJD;
  		
  		public TimeStamp(double MJD) { this.MJD = MJD; }
  		
  		public TimeStamp(int iMJD, String hhmmsss) { 
  			this.MJD = iMJD + (
  						Integer.parseInt(hhmmsss.substring(0, 2)) * Unit.hour +
  						Integer.parseInt(hhmmsss.substring(3, 5)) * Unit.min + 
  						Double.parseDouble(hhmmsss.substring(6)) * Unit.s
  					) / Unit.day; 
  		}
  		
  		@Override
  		public double distanceTo(Locality other) {
  			return(Math.abs((((TimeStamp) other).MJD - MJD) * Unit.day / timeWindow));
  		}
  
  		@Override
  		public int compareTo(Locality o) {
  			return Double.compare(MJD, ((TimeStamp) o).MJD);
  		}
  		
  		@Override
  		public String toString() { return Double.toString(MJD); }
  
  		@Override
  		public double sortingDistanceTo(Locality other) {
  			return distanceTo(other);
  		}
  	}
  
  	
  	class Entry extends LocalizedData {
  		/**
  		 * 
  		 */
  		private static final long serialVersionUID = -3204359502356393498L;
  		TimeStamp timeStamp;
  		DataPoint tau = new DataPoint();
  		
  		
  		@Override
  		public Locality getLocality() {
  			return timeStamp;
  		}
  
  		@Override
  		public void setLocality(Locality loc) {
  			timeStamp = (TimeStamp) loc;
  		}
  
  		@Override
  		protected void averageWidth(LocalizedData other, Object env, double relativeWeight) {
  			Entry entry = (Entry) other;
  			tau.average(entry.tau.value(), relativeWeight * entry.tau.weight());
  		}	
  	}
  
  	@Override
  	public Entry getLocalizedDataInstance() {
  		return new Entry();
  	}
  	
  }
  
  
  