標準偏差

public static double getSD(int[] x){
    //算術平均の算出
    double ave = 0;
    for(int i = 0; i < x.length; i++){
        ave = ave + x[i];
    }
    ave = ave / (x.length);

    //分散の算出
    double sum = 0;
    for(int i = 0; i < x.length; i++){
        sum = sum + (Math.abs(x[i] - ave) * Math.abs(x[i] - ave));
    }
    sum = sum / (x.length);

    return Math.sqrt(sum);
}