How to use

nextInt

method

in

org.apache.commons.math3.random.MersenneTwister

  public void randomize () {
    for (TIntObjectIterator<int[]> it = offsets.iterator(); it.hasNext();) {
      it.advance();
      int[] newVal = new int[it.value().length];

      RaptorWorkerTimetable tt = data.timetablesForPattern.get(it.key());

      for (int i = 0; i < newVal.length; i++) {
        newVal[i] = mt.nextInt(tt.headwaySecs[i]);
      }

      it.setValue(newVal);
    }

  }
}

@Override
public int nextInt(int lowerBound, int upperBound) {
 return lowerBound + rnd.nextInt((upperBound - lowerBound) + 1) ;
}

public int nextInt() { return this.myPrg.nextInt(); }

public int nextInt(int range) { return this.myPrg.nextInt(range); }

private ArrayList<Integer> generateDepartureTimesToSample (ProfileRequest request) {
  // See Owen and Jiang 2016 (unfortunately no longer available online), add between f / 2 and
  // f + f / 2, where f is the mean step.
  int randomWalkStepMean = (request.toTime - request.fromTime) / request.monteCarloDraws;
  int randomWalkStepWidthOneSided = randomWalkStepMean / 2;
  ArrayList<Integer> departureTimes = new ArrayList<>();
  for (int departureTime = request.fromTime + mersenneTwister.nextInt(randomWalkStepMean);
     departureTime < request.toTime;
     departureTime += mersenneTwister.nextInt(randomWalkStepMean) + randomWalkStepWidthOneSided) {
    departureTimes.add(departureTime);
  }
  return departureTimes;
}

private ArrayList<Integer> generateDepartureTimesToSample (ProfileRequest request) {
  // See Owen and Jiang 2016 (unfortunately no longer available online), add between f / 2 and
  // f + f / 2, where f is the mean step.
  int randomWalkStepMean = (request.toTime - request.fromTime) / request.monteCarloDraws;
  int randomWalkStepWidthOneSided = randomWalkStepMean / 2;
  ArrayList<Integer> departureTimes = new ArrayList<>();
  for (int departureTime = request.fromTime + mersenneTwister.nextInt(randomWalkStepMean);
     departureTime < request.toTime;
     departureTime += mersenneTwister.nextInt(randomWalkStepMean) + randomWalkStepWidthOneSided) {
    departureTimes.add(departureTime);
  }
  return departureTimes;
}

/**
 * @return the next pseudorandom Geometric with distribution parameter p. Should be more
 * efficient than using logs.
 */
public int nextGeometric(double p) {
  if (p <= 0) throw new IllegalArgumentException("parameter of Geometric Distribution must be positive");
  int value = myPrg.nextInt();
  double sample = (double) Math.abs(value) / Integer.MAX_VALUE;
  return (int) (Math.floor((Math.log(1 - sample) / Math.log(1-p) ) )) + 1;
}

/**
 * Helper method that generates a List of random alphanumeric strings.
 * @param suppSize Number of strings
 * @param length Size of each string.
 */
public static List<String> randStringList(int suppSize, int length) {
  String aToZ = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
  MersenneTwister random = new MersenneTwister(2);
  ArrayList<String> names = new ArrayList<String>();
  for (int i = 0; i < suppSize; i++) {
    StringBuilder nextName = new StringBuilder();
    for (int j = 0; j < length; j++) {
      int index = random.nextInt(aToZ.length());
      nextName.append(aToZ.charAt(index));
    }
    names.add(nextName.toString());
  }
  return names;
}

 MersenneTwister rng = new MersenneTwister();
rng.setSeed(new int[] {1234567890});
System.out.println(rng.nextInt(Integer.MAX_VALUE)); // 1977150888

char[] chars = new char[length];
for (int i = 0; i < length; i++) {
  chars[i] = (char) ('a' + twister.nextInt(26));

val[tripScheduleIndex][frequencyEntryIndex] = mt.nextInt(schedule.headwaySeconds[frequencyEntryIndex]);
remaining--;

val[tripScheduleIndex][frequencyEntryIndex] = mt.nextInt(schedule.headwaySeconds[frequencyEntryIndex]);
remaining--;