rowStd
语法
rowStd(args...)
row 系列函数通用参数说明和计算规则请参考:rowFunctions
详情
逐行进行元素求样本标准差操作,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])
rowStd(m);
# output
[1.858315,1.474223,3.11127]
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);
rowStd(t1);
# output
[4.725816,3.785939,2.886751,2.081666,1.527525]
rowStd(t1[`x], t2, 1 1 2 2 2);
# output
[3.114482,3.04959,2.949576,3.316625,3.834058]
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,rowStd(price1,price2) as std from t;
sym | std |
---|---|
AAPL | 88.833825 |
MS | 15.061374 |
IBM | 14.707821 |
IBM | 15.040161 |
C | 105.175063 |