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Lou Montana (talk | contribs) m (Text replacement - "\[\[([a-zA-Z][a-zA-Z0-9_]+)\]\]([^ ]*)<\/code>" to "$1$2</code>") |
Lou Montana (talk | contribs) m (Text replacement - "<code>([^ ]*)\[\[([a-zA-Z][a-zA-Z0-9_]+)\]\]([^ ]*) ([^ ]*) ([^ ]*)<\/code>" to "<code>$1$2$3 $4 $5</code>") |
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* The number returned is unlikely to be a whole number.<br> | * The number returned is unlikely to be a whole number.<br> | ||
To return a whole number use either '''[[round]]''', '''[[ceil]]''' or '''[[floor]]''' together with [[random]]: | To return a whole number use either '''[[round]]''', '''[[ceil]]''' or '''[[floor]]''' together with [[random]]: | ||
<code>x = | <code>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 = [[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)</code> | x = ceil (random 5) will return 0, 1, 2, 3, 4 or 5. (0 is very unlikely, but possible, as ceil 0 is 0)</code> |
Revision as of 11:43, 12 May 2022
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 seed-based random number Syntax 4 generates a seed-based 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
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 (excluded)
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:
_rNumber = random -10;
- Example 3:
- Generate a random position inside a circle (see also Example Code: Random Area Distribution)
_center getPos [_radius * sqrt random 1, random 360];
- 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 Template:arma3 v1.56
Additional Information
- See also:
- selectRandom selectRandomWeighted
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 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.
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)
- Posted on July 22, 2018 - 12:58 (UTC+2)
- Lou Montana
-
Repartition comparison Formula 0 1 2 3 4 5 6 7 8 9 floor random 10; 10% 10% 10% 10% 10% 10% 10% 10% 10% 10% floor random [0, 5, 10] 0% 2% 7% 17% 25% 25% 17% 7% 2% 0% floor random [0, 10, 0] 0% 0% 1% 2% 5% 9% 14% 19% 24% 26% floor random [0, 10, 5] 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