用java代码实现数学公式计算数据

 
  public static double correl(List array1, List array2) {

    double top = 0;

    double lowX = 0;
    double lowY = 0;

    double sumX = 0;
    double sumY = 0;

    for (double v : array1) {
      sumX += v;
    }

    for (double v : array2) {
      sumY += v;
    }
    double avgX = sumX / array1.size();
    double avgY = sumY / array2.size();

    for (int i = 0; i < array1.size(); i++) {
      top += (array1.get(i) - avgX) * (array2.get(i) - avgY);
      lowX += (array1.get(i) - avgX) * (array1.get(i) - avgX);
      lowY += (array2.get(i) - avgY) * (array2.get(i) - avgY);
    }

    double correlData = top / (Math.sqrt(lowX * lowY));

    return correlData;
  }