Java Average, Jumps

I'm a complete Java newbie. Started Last Monday and have never done any programming in any language before. So please bear with me if I find easy things complicated.

I've been given a text file. As shown below:

The First piece of data is time (in seconds past midnight), the second is score (irrelevant), the third is Jump (dont need to know what this means...)

I can happily read this in using this code:

import java.io.FileReader;
import java.io.BufferedReader;
import java.util.ArrayList;



 public class ReadText {

  public static void main(String[] args) throws Exception {

   String InputFile="C:\\PracticeSpreads.txt";
   ArrayList<String> fileLines=new ArrayList<String>();
   FileReader fr;
   BufferedReader br;
   fr = new FileReader(InputFile);
   br = new BufferedReader(fr);
   String line;
   br.readLine();

   while ((line=br.readLine()) != null) {

   fileLines.add(line);

   //System.out.print(line+"\n");



 }

 }
 }

I skipped the first line because it makes it easier.

Ok basically what I need to do is create a Daily Time weighted Average Jump.

I can get an average Jump but not a time weighted average Jump.

The formula for time weighted average jump is=

For times when a second has more than one Jump, I want to take the "average jump" for that time period.

But I've literally got no idea as I'm not too sure as to how the开发者_运维知识库 loops would arrange themselves.

Hopefully someone can help me please!

---

After reading your comments bellow and understanding your requirement better, here is a piece of code that does the job. Note that it assumes that the timestamps in each day are sorted, as in your example:

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
import java.util.AbstractMap.SimpleEntry;

public class ReadText {
    public static void main(String[] args) throws IOException {
        BufferedReader br = null;
        try {
            String InputFile = "C:\\PracticeSpreads.txt";
            br = new BufferedReader(new FileReader(InputFile));
            String line;
            List<SimpleEntry<Integer, List<Double>>> valuesInDay = new ArrayList<SimpleEntry<Integer, List<Double>>>();
            String date = null;
            while ((line = br.readLine()) != null) {
                line = line.trim();
                if (line.startsWith("DATE")) {
                    if (line.equals(date)) // Found day footer
                        System.out.println("Average for " + date + ": " + calcDayAvg(valuesInDay));
                    else { // Found a day header
                        valuesInDay.clear();
                        date = line;
                    }
                } else { // Found a value entry
                    Scanner s = new Scanner(line);
                    int sec = s.nextInt();
                    s.nextDouble();
                    double jump = s.nextDouble();

                    List<Double> jumps;
                    if (!valuesInDay.isEmpty() && valuesInDay.get(valuesInDay.size() - 1).getKey() == sec) {
                        // Same time stamp as prev
                        jumps = valuesInDay.get(valuesInDay.size() - 1).getValue();
                    }else { 
                        // New time stamp
                        jumps = new ArrayList<Double>();                        
                        valuesInDay.add(new SimpleEntry<Integer, List<Double>>(sec, jumps));
                    }
                    jumps.add(jump);
                }
            }
        } finally {
            if (br != null)
                br.close();
        }
    }

    private static Double calcDayAvg(List<SimpleEntry<Integer, List<Double>>> values) {
        if (values.isEmpty())
            return null; // No way to calculate for empty set
        double min = values.get(0).getKey();
        double max = values.get(values.size() - 1).getKey();
        double span = max - min;
        if (span == 0)
            return null; // Division by zero...     

        double total = 0;
        for (int i=0; i < values.size(); i++) {
            SimpleEntry<Integer, List<Double>> entry = values.get(i);
            int sec = entry.getKey();
            double jumpAvg = getJumpAvg(entry.getValue());
            int jumpDuration;
            if (i == values.size() - 1)
                jumpDuration = 1; // last jump has duration of 1 sec
            else
                jumpDuration = values.get(i + 1).getKey() - sec;

            total += jumpAvg * jumpDuration;
        }
        return total / span;
    }

    private static double getJumpAvg(List<Double> jumps) {
        double total = 0;
        for (Double jump : jumps) {
            total += jump;
        }
        return total / jumps.size();
    }
}