Here’s how to use ptop() function.
Description:
Get the sequence numbers of the n smallest members in a sequence.
Syntax:
A.ptop(n,x)
Note:
The function sorts members of sequence A according to expression x and returns a sequence comprising the sequence numbers of the n smallest members in the given sequence. List both if the smallest member and the largest member are the same. n must be supplied; if n is 0, return null. The absence of x is equivalent to ~; and if the value of x is 0, sorting action won’t be performed.
Parameters:
A |
A sequence |
x |
Sorting expression |
n |
An integer |
Options:
@1 |
Return a single value if n is ±1 |
Return value:
A sequence composed of sequence numbers of specified members
Example:
|
A |
|
1 |
[a,c,e,g,f,d,b] |
|
2 |
=A1.ptop(3,~) |
[1,7,2] |
3 |
=A1.ptop(3) |
Same as A2, as x is not supplied |
4 |
=demo.query("select * from EMPLOYEE") |
|
5 |
=A4.ptop(3,HIREDATE) |
[8,18,203] |
6 |
=A1.ptop(-1) |
|
7 |
=A4.ptop(3,0) |
[1,2,3] |
8 |
=A1.ptop@1(-1) |
|
9 |
[a,c,e,g,f,d,b,a] |
|
10 |
=A9.ptop(1,~) |
[1,8] |
Related functions: