3.5.2.1.34 Fact

Description

This function is used to calculate the factorial of a non-negative integer, denoted by:

n! = n\left (n-1  \right )\left (n-2\right )...1

For zero, Fact(0) = 1.

Please note that the largest n is 170. If n is bigger than 170, this function will return missing value. To calculate factorial for the larger integer, you can use the Log_gamma function, which approximates a factorial.

Syntax

double Fact(int n)

Parameters

n

The integer number for calculating the factorial.

Return

Return the factorial of a non-negative integer n.

Example

fact(3) = ;  // 6
fact(170) = ;  // 7.257415615308E306
fact(171) = ;  // n is too big, return missing value --

See Also

FactDouble