# nchoosek

Combinatorial function for selecting from a set of items.

## Syntax

C=nchoosek(n,k)

C=nchoosek(v,k)

## Inputs

`n`- The number of items from which to choose.
`v`- The list of items from which to choose.
`k`- The number of items to choose.

## Outputs

- C
- The number of combinations or the list of combinations stored by row.

## Examples

Number of combinations example:

`C = nchoosek(9,4)`

`C = 126`

List of combinations example:

`C = nchoosek([10,20,30,40,50],3)`

```
C = [Matrix] 10 x 3
10 20 30
10 20 40
10 20 50
10 30 40
10 30 50
10 40 50
20 30 40
20 30 50
20 40 50
30 40 50
```