topRange

Syntax

topRange(X)

Arguments

X is a vector/tuple/matrix/table

Details

For each element Xi in X, count the continuous nearest neighbors to its left that are larger than Xi.

For each element in X, the function return the maximum length of a window to the left of X where it is the max/min. For example, after how many days a stock hits a new high.

Examples

$ topRange([13.5, 13.6, 13.4, 13.3, 13.5, 13.9, 13.1, 20.1, 20.2, 20.3])
[0,1,0,0,2,5,0,7,8,9]

$ m = matrix(1.5 2.6 3.2 1.4 2.5 2.2 3.7 2.0, 1.6 2.3 4.2 5.6 4.1 3.2 4.4 6.9)
$ topRange(m)

#0	#1
0	0
1	1
2	2
0	3
1	0
0	0
6	2
0	7

//Simulate the stock price of stock A for 8 days. Use topRange to calculate after how many days the stock hit a new high
$ trades = table(take(`A, 8) as sym,  2022.01.01 + 1..8 as date, 39.70 39.72 39.80 39.78 39.83 39.92 40.00 40.03 as price)
$ select *, topRange(price) from trades

id	date	price	topRange_price
A	2022.01.02	39.7	0
A	2022.01.03	39.72	1
A	2022.01.04	39.8	2
A	2022.01.05	39.78	0
A	2022.01.06	39.83	4
A	2022.01.07	39.92	5
A	2022.01.08	40	6
A	2022.01.09	40.03	7

Related function: lowRange