factorial#
Purpose#
Computes the factorial of a number.
Format#
y = n!
Parameters#
- param n:
Input value (truncated to integer).
- type n:
scalar, vector, or matrix
Returns#
- return y:
Factorial of each element, n! = n * (n-1) * (n-2) * … * 1.
- rtype y:
same dimensions as input
Examples#
y = 5!;
y = 120.00000
x = { 0, 1, 2, 3, 4, 5 };
y = x!;
y = 1.0000000
1.0000000
2.0000000
6.0000000
24.0000000
120.0000000
In Expressions#
// Combinations: n choose k = n! / (k! * (n-k)!)
n = 5;
k = 2;
combinations = n! / (k! * (n-k)!);
combinations = 10.000000
Remarks#
The factorial is defined only for non-negative integers.
0! = 1 by definition.
For large values, the result may overflow to infinity.
For the gamma function (generalized factorial), use
gamma()where gamma(n+1) = n!.