random
Jump to navigation
Jump to search
Description
 Description:

Syntax 1 generates a random floating point value Syntax 2 generates a Gaussian Distribution^{[1]}. It uses the same method as setTriggerTimeout command and is quite useful for e.g spawning loot, making more valuable items more rare Syntax 3 generates a seedbased random number Syntax 4 generates a seedbased random noise (not Perlin) texture based on provided seed and returning the value at supplied coordinates  Groups:
 Math
Syntax 1
Syntax 2
 Syntax:
 random [min, mid, max]
 Parameters:
 min: Number
 mid: Number
 max: Number
 Return Value:
 Number in range from min to max, weighted by mid  can be higher than max (maximum value is min + max  mid)
Syntax 3
 Syntax:
 seed random x
 Parameters:
 seed: Number  an integer. Any float value will be truncated (e.g 0.9, 0.1, 0.1 or 0.9 will be read as 0)
 x: Number
 Return Value:
 Number from 0 (included) to x (included)
Syntax 4
 Syntax:
 seed random [x, y]
 Parameters:
 seed: Number
 x: Number  x texture position
 y: Number  y texture position
 Return Value:
 Number from 0 (included) to 1 (excluded)
Examples
 Example 1:
 Example 2:
 Example 3:
 Generate a random position inside a circle (see also Example Code: Random Area Distribution)
 Example 4:
 Select a random value from an array:
_array = ["apples", "pears", "bananas", "M16"]; _random = _array select floor random count _array; // before Arma 2 _random = _array call BIS_fnc_selectRandom; // since Arma 2 _random = selectRandom _array; // since Arma 3 v1.56
 Example 5:
 Visualisation of Syntax 4 (warning, it takes a bit to execute and draw):
private _parent = call BIS_fnc_displayMission; if (is3DEN) then { _parent = findDisplay 313 }; private _display = _parent createDisplay "RscDisplayEmpty"; private _background = _disp ctrlCreate ["RscBackground", 1]; private _coef = 0.1; for "_x" from 1 to 100 do { for "_y" from 1 to 100 do { private _random = 0 random [_x * _coef, _y * _coef]; private _dot = _display ctrlCreate ["RscBackground", 1]; _dot ctrlSetPosition [0.5 + pixelW * _x, 0.5 + pixelH * _y, pixelW, pixelH]; _dot ctrlSetBackgroundColor [_random, _random, _random, 1]; _dot ctrlCommit 0; }; };
Additional Information
Notes

Report bugs on the Feedback Tracker and/or discuss them on the Arma Discord or on the Forums.
Only post proven facts here! Add Note
 Posted on Jul 12, 2015  20:32 (UTC)

Random selections including negative numbers can be obtained via:
This will yield numbers between 100 and 100.
 Be careful using random numbers in multiplayer, each client will come up with a different result. See multiplayer tutorials for more general information about locality.
 The number returned is unlikely to be a whole number.
x = round (random 5) // will return 0, 1, 2, 3, 4 or 5. (nonuniform distribution, 0 and 5 are half as likely to be selected than any of the other numbers) x = floor (random 5) // will return 0, 1, 2, 3 or 4. (uniform distribution, all numbers have the same probability of being selected) x = ceil (random 5) // will return 0, 1, 2, 3, 4 or 5. (0 is very unlikely, but possible, as ceil 0 is 0)
 Posted on Jul 22, 2018  12:58 (UTC)

Repartition comparison Formula 0 1 2 3 4 5 6 7 8 9 10% 10% 10% 10% 10% 10% 10% 10% 10% 10% 0% 2% 7% 17% 25% 25% 17% 7% 2% 0% 0% 0% 1% 2% 5% 9% 14% 19% 24% 26% 0% 0% 0% 1% 2% 5% 9% 16% 28% 38%
 ↑ Technically, it is a rescaled Bates distribution with n = 4. The distribution is split in two at its midpoint and scaled linearly such that its maximum lies at the specified midpoint.
Categories:
 Scripting Commands
 Introduced with Operation Flashpoint version 1.00
 Operation Flashpoint: New Scripting Commands
 Operation Flashpoint: Scripting Commands
 Operation Flashpoint: Elite: Scripting Commands
 ArmA: Armed Assault: Scripting Commands
 Arma 2: Scripting Commands
 Arma 2: Operation Arrowhead: Scripting Commands
 Take On Helicopters: Scripting Commands
 Arma 3: Scripting Commands
 Command Group: Math