How to obtain factorial of a variable?

[BlueMoon]

I would like to get factorial of my variables? Can you help me find this?

Example:
If my variable had values 2,5

2 = 2 X 1
5 = 5 X 4 X 3 X 2 X1 = 80

[miro1360]

create simple custom code

[fxDreema]

I don't even remember what factorial is, I'm so bad in math There are some Math functions in MQL already, but even if there is no function like this, you can try to make your own function (somewhere in /studio) and use it in the code