private static HashMap<Integer, Holder> getMap(File file, int dataColNum) throws Exception
	{
		HashMap<Integer, Holder> map = new HashMap<Integer, Holder>();
		BufferedReader reader = new BufferedReader(new FileReader(file));
		
		reader.readLine();
		
		for(String s = reader.readLine(); s != null && s.trim().length() > 0 ; s = reader.readLine())
		{
			String[] splits = s.split("\t");
			
			Integer patientId = Integer.parseInt(splits[0]);
			
			Holder h = map.get(patientId);
			
			if( h == null)
			{
				h = new Holder();
				map.put(patientId, h);
			}
			
			int time = Integer.parseInt(splits[1]);
			
			if( time == 1)
			{
				if( h.time1 != null)
					throw new Exception("no");
				
				h.time1 = Double.parseDouble(splits[dataColNum]);
			}
			else if (time == 2) 
			{
				if( h.time2 != null)
					throw new Exception("no");
				
				h.time2 = Double.parseDouble(splits[dataColNum]);
			}
			else throw new Exception("No");
		}
		
		reader.close();
		return map;
	}