rowVar
语法
rowVar(args…)
row 系列函数通用参数说明和计算规则请参考: 行计算系列(row 系列)
详情
逐行进行元素求样本方差操作,返回一个长度与输入参数行数相同的向量。
例子
$ m=matrix([4.5 2.6 1.5, 1.5 4.8 5.9, 4.9 2.0 NULL]);
$ rowVar(m);
[3.453333,2.173333,9.68]
$ t1=table(1..5 as x, 10..6 as y, take(3, 5) as z);
$ t2=table(5..1 as a, 6..10 as b, take(8, 5) as c);
$ rowVar(t1);
[22.333333,14.333333,8.333333,4.333333,2.333333]
$ rowVar(t1[`x], t2, 1 1 2 2 2);
[9.7,9.3,8.7,11,14.7]
$ t=table(`AAPL`MS`IBM`IBM`C as sym, 49.6 29.46 29.52 30.02 174.97 as price1, 175.23 50.76 50.32 51.29 26.23 as price2);
$ select sym,rowVar(price1,price2) as var from t;
sym |
var |
---|---|
AAPL |
7891.44845 |
MS |
226.845 |
IBM |
216.32 |
IBM |
226.20645 |
C |
11061.7938 |