求方差

遍历求方差

public static void main(String[] args) {
        float []a={11,12,13,14,15,16};//数组
       float ava=0;//平均数

计算平均数的循环
        for (int i = 0; i <a.length; i++) {
            ava+=a[i];
        }
        ava/=a.length;

计算方差的循环
        float diff = 0;
        for (int i = 0; i < a.length; i++) {
            diff+=(a[i]-ava)*(a[i]-ava);
        }
        diff/=a.length;

        System.out.println(diff);
    }