PERM

PERM

Computes the number of permutations of n items taken r at a time and returns a value

Category: Mathematical

Syntax

PERM(n<,r>)

n

is an integer that represents the total number of elements from which the sample is chosen.

r

is an optional integer value that represents the number of chosen elements. If r is omitted, the function returns the factorial of n.

Restriction:

Details

The mathematical representation of the PERM function is given by the following equation:

[IMAGE]

with n [ge] 0, r [ge] 0, and n [ge] r.

If the expression cannot be computed, a missing value is returned.

SAS Statements Result

x=perm(5,1);
5

x=perm(5);
120

x=perm(5,2)
20

See Also

Functions:

COMB

FACT