public static double generateRandomDoubleBetween(double lowerLimit,double upperLimit){
  return lowerLimit + ((upperLimit - lowerLimit) * _r.nextDouble());
}

public static double generateRandomDoubleBetween ( double lowerLimit , double upperLimit ) { return lowerLimit + ( ( upperLimit - lowerLimit ) * _r . nextDouble ( ) ) ; }
generates a random double between two limits . both limits are inclusive .
