MATLAB Function Reference | ![]() ![]() |
Binomial coefficient or all combinations
Syntax
C = nchoosek(n,k) C = nchoosek(v,k)
Description
C = nchoosek(n,k)
where n
and k
are nonnegative integers, returns n! / ( (n-k)! k!). This is the number of combinations of n things taken k at a time.
C = nchoosek(v,k),
where v
is a row vector of length n
, creates a matrix whose rows consist of all possible combinations of the n elements of v
taken k at a time. Matrix C
contains n! / ( (n-k)! k!) rows and k columns.
Examples
The command nchoosek(2:2:10,4)
returns the even numbers from two to ten, taken four at a time:
2 4 6 8 2 4 6 10 2 4 8 10 2 6 8 10 4 6 8 10
Limitations
This function is only practical for situations where n
is less than about 15.
See Also
![]() | nargoutchk | ndgrid | ![]() |