XLeratorDB/statistics Documentation
Updated: 30 May 2017
Use the SQL Server scalar function PERMUTATIONA to calculate the number of permutations with replacement defined as:
Syntax
SELECT [wct].[PERMUTATIONA] (
<@n, int,>
,<@k, int,>)
Arguments
| Input Name | Definition |
| @n | Number of items |
| @k | Number chosen |
Return Type
Remarks
Examples
Example #1
SELECT wct.PERMUTATIONA(10,3) as PERMUTATIONA
This produces the following result.
Example #2
Calculate the probability of 2 people having the same birthday in a room containing n people.
SELECT
x.n
,1 - wct.PERMUT(365,x.n)/wct.PERMUTATIONA(365,x.n) as [p(n)]
FROM (VALUES
(10),(20),(22),(23),(30),(57))x(n)
This produces the following result.
See Also