testdice.java

MegaMek is a networked Java clone of BattleTech, a turn-based sci-fi boardgame for 2+ players. Fight

package megamek.test;

import megamek.common.Compute;

public class TestDice {

    public static void testDice() {
        // test RNG
        long rolls = 1000000;
        long[] hits = new long[11];
    
        System.out.println("testing dice, " + rolls + " rolls...");
    
        long start = System.currentTimeMillis();
        for (long i = 0; i < rolls; i++) {
            hits[megamek.common.Compute.d6(2)-2]++;
        }
        long end = System.currentTimeMillis();
    
        System.out.println("done testing dice in " + (end - start) + " ms.");
        for (int i = 0; i < hits.length; i++) {
            System.out.println(
                "hits on " + (i+2) + " : " + hits[i] + "; probability = " + ((double) hits[i] / (double) rolls));
        }
    
        int[][] pairs = new int[6][6];
        System.out.println("testing streaks, " + rolls + " rolls...");
    
        int nLastLastRoll = 1;
        for (long i = 0; i < rolls; i++) {
            int nRoll = Compute.d6();
            pairs[nLastLastRoll - 1][nRoll - 1]++;
            nLastLastRoll = nRoll;
        }
        for (int x = 0; x < pairs.length; x++) {
            for (int y = 0; y < pairs[x].length; y++) {
                System.out.println((x+1) + "," + (y+1) + ": " + pairs[x][y]);
            }
        }
        // odd, but necessary
        System.out.flush();
    }
    
    public static void main(String[] args) {
        testDice();
    }

}