signum
¶
signum x signum[x]
Where x
(or its underlying value for temporals) is
- null or negative, returns
-1i
- zero, returns
0i
- positive, returns
1i
q)signum -2 0 1 3
-1 0 1 1i
q)signum (0n;0N;0Nt;0Nd;0Nz;0Nu;0Nv;0Nm;0Nh;0Nj;0Ne)
-1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1i
q)signum 1999.12.31
-1i
Find counts of price movements by direction:
select count i by signum deltas price from trade
signum
is a multithreaded primitive.
Implicit iteration¶
signum
is an atomic function.
q)signum(10;-20 30)
1i
-1 1i
q)k:`k xkey update k:`abc`def`ghi from t:flip d:`a`b!(10 -21 3;4 5 -6)
q)signum d
a| 1 -1 1
b| 1 1 -1
q)signum t
a b
-----
1 1
-1 1
1 -1
q)signum k
k | a b
---| -----
abc| 1 1
def| -1 1
ghi| 1 -1
Domain and range¶
domain b g x h i j e f c s p m d z n u v t
range i . i i i i i i i . i i i i i i i i
Range: i