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PORandomWalk - New task
 

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  1. PORandomWalk - New task
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    <p>I've come again to ask for your help. I have this piece of code:</p> <pre><code>import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.FileWriter; import java.io.PrintStream; import java.io.PrintWriter; import java.util.HashMap; public class RandomWalk { public static final int NBR_WALKS = 1000; public static final int NBR_STEPS = 500; public static void main(String[] args) { /*PrintStream out; try { out = new PrintStream(new FileOutputStream("/Volumes/DATA/Desktop/RandomWalkResultater.txt", true)); System.setOut(out); } catch (FileNotFoundException e) { e.printStackTrace(); }*/ HashMap&lt;Integer, Integer&gt; totals = new HashMap&lt;&gt;(); for (int i = -NBR_STEPS; i &lt;= NBR_STEPS; i++) { totals.put(i, 0); } System.out.println(""); for (int i = 0; i &lt; NBR_WALKS; i++) { int total_value = 0; for (int j = 0; j &lt; NBR_STEPS; j++) { int L = (int) (Math.random() * 2); total_value += (L == 0) ? -1 : 1; } System.out.println("For randomwalk nummer " + i + " var slut punktet " + total_value); totals.put(total_value, totals.get(total_value) + 1); } System.out.println(" "); for (int i = -500; i &lt; 500; i++) { System.out.println("Du landede på slut punktet "+i+" følgende gange: "+totals.get(i)); } System.out.println(" "); System.out.println("Til excel arket:"); System.out.println("x-værdierne:"); for (int i = -500; i &lt; 500; i++) { System.out.println(i); } System.out.println(""); System.out.println("y-værdierne:"); for (int i = -500; i &lt; 500; i++) { System.out.println(totals.get(i)); } } } </code></pre> <p>And I need to add a feature. I want this program to output the following (I've tried and I don't think I completely understand it because it's not doing as I want):</p> <p>The average value. It'll do 1000 walks with 500 steps in them, so theoretically it could end up in -500 or +500. So to calculate the average value I need to say (let's call it a) a = ((Where it landed * how many times it landed on that spot)+(Where it landed+1 * how many times it landed on that spot+1)+..)/number of walks, in this case 1000)</p> <p>Example: a = ((-500*0)+(-499*0)...(10*3)...(500*0))/(1000)</p> <p>Can you please help me with this? I've tried for over a day and I can't seem to wrap it up :(</p>
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    1. USPaludan
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    1. CO_it's not doing as I want_ is not a very good problem description. What, specifically, is the problem with the code you have produced?
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      1. PORandomWalk - New task
      1. USKeppil
    2. COcan't you just divide total_value/NBR_WALKS ?
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      1. PORandomWalk - New task
      1. USPepe
    3. COThe code right there is doing exactly what it's supposed to do. But the code I added (I deleted it because it wasn't working) which should have done the feature of outputting the average value, didn't work. I need help creating this average value code. :) Thank you, it's for a school project to help me calculate the position (most likely position) of an electron:P
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      1. PORandomWalk - New task
      1. USPaludan
 

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