mwsumTopN

语法

mwsumTopN(X, Y, S, window, top, [ascending=true], [tiesMethod='oldest'])

参数说明和窗口计算规则请参考:mTopN

详情

在给定长度(以元素个数衡量)的滑动窗口内,根据 ascending 指定的排序方式将 XY 按照 S 进行稳定排序后,取前 top 个元素,然后计算 YX 的内积。

例子

x = NULL 3 8 4 0 7 4
y = 2 3 1 7 3 6 1
s = 5 NULL 8 9 9 4 4

mwsumTopN(x, y, s, 4, 3)
// output
[,,8,36,36,78,74]

s2=2021.01.01 2021.02.03 2021.01.23 2021.04.06 2021.12.29 2021.04.16 2021.10.29
mwsumTopN(x, y, s2, 3, 2)
// output
[ , 9, 8, 17, 36, 70, 46]

x1 = matrix(x, 4 3 6 2 3 1 3)
y1=matrix(3 7 9 3 2 4 6, y)
s1=matrix(2 3 1 7 3 NULL 1, s)

mwsumTopN(x1,y1,s1,4,3)
#1 #2
8
21 8
93 14
93 28
93 29
84 26
36 23
mwsumTopN(x1, y1, s, 4, 3)
#1 #2
8
8
72 14
84 28
84 29
112 26
64 23
n = 3000
ids = 1..3000
dates = take(2021.01.01..2021.10.01,n)
prices = rand(1000,n)
vals = rand(1000,n)
t = table(ids as id,dates as date,prices as price,vals as val)
dbName = "dfs://test_mwsumTopN_2"
if(existsDatabase(dbName))dropDB(dbName)
db = database(dbName,VALUE,1..5000)
pt = db.createPartitionedTable(t,"pt",`id).append!(t)
select mwsumTopN(price, val, id, 10, 5, true) from pt where date>2021.05.01

相关函数:mwsum