random

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Description

Description:
bellcurve.jpg
Random real (floating point) value from 0 (inclusive) to x (not inclusive).

Since Arma 3 v1.55.133393 alternative syntax is added, allowing to define Gaussian Distribution params. Uses the same method as setTriggerTimeout command. Quite useful for spawning loot for example, making more valuable items more rare.

Since Arma 3 v1.67.139663 an alternative syntax is available, allowing to generate semi-random number based on provided seed.

Since Arma 3 v1.67.139663 an alternative syntax is available, generating pseudo-random noise texture based on provided seed and returning a single number between 0 (included) and 1 (excluded) at supplied x and y coordinates.
Groups:
Uncategorised

Syntax 1

Syntax:
random x
Parameters:
x: Number
Return Value:
Number

Syntax 2

Syntax:
random [min, mid, max]        (Since Arma 3 v1.55.133393)
Parameters:
[min, mid, max]: Array
min: Number
mid: Number
max: Number
seed: Number
x: Number
Return Value:
Number

Syntax 3

Syntax:
seed random x        (Since Arma 3 v1.67.139663)
Parameters:
seed: Number
[x, y]: Array
x: Number
y: Number
Return Value:
Number

Syntax 4

Syntax:
seed random [x,y]        (Since Arma 3 v1.67.139663)
Return Value:
Number

Examples

Example 1:
_rNumber = random 1;
Example 2:
_rNumber = random -10;
Example 3:
To select random value from an array: _array = ["apples", "pears", "bananas", "M16"]; _random = _array select floor random count _array; // or since Arma 3 v1.55.133393 _random = selectRandom _array;
Example 4:
Compare (each command was executed 100000 times to gather statistics):floor random 10; // 0 - 10099 (10%) // 1 - 10040 (10%) // 2 - 10154 (10%) // 3 - 9910 (10%) // 4 - 10023 (10%) // 5 - 9937 (10%) // 6 - 10118 (10%) // 7 - 9716 (10%) // 8 - 9986 (10%) // 9 - 10017 (10%) floor random [0,5,10]; // 0 - 109 (0%) // 1 - 1604 (2%) // 2 - 6839 (7%) // 3 - 16671 (17%) // 4 - 24706 (25%) // 5 - 24702 (25%) // 6 - 16626 (17%) // 7 - 6925 (7%) // 8 - 1702 (2%) // 9 - 116 (0%) floor random [0,10,0]; // 0 - 19 (0%) // 1 - 209 (0%) // 2 - 817 (1%) // 3 - 2384 (2%) // 4 - 4841 (5%) // 5 - 8976 (9%) // 6 - 14067 (14%) // 7 - 18955 (19%) // 8 - 23605 (24%) // 9 - 26127 (26%) floor random [0,10,5]; // 0 - 11 (0%) // 1 - 98 (0%) // 2 - 430 (0%) // 3 - 1149 (1%) // 4 - 2384 (2%) // 5 - 4546 (5%) // 6 - 8612 (9%) // 7 - 16283 (16%) // 8 - 28393 (28%) // 9 - 38094 (38%)

Additional Information

See also:
Math CommandsselectRandom

Notes

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Notes

Posted on July 12, 2015 - 20:32 (UTC)
Hcpookie
Random selections including negative numbers can be obtained via: _Xrnd = round(random 200) -100; 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.
    To return a whole number use either round, ceil or floor together with random:
x=round(random 5) will return 0,1,2,3,4 or 5. (non-uniform 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)