random: Difference between revisions
Bovine3dom (talk | contribs) m (Added link to correct distribution for people who would be very confused at the concept of a minimum and maximum for a normal distribution.)  | 
				Bovine3dom (talk | contribs)  m (Corrected distribution)  | 
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|[[Image:bellcurve.jpg|right|200px]] Random real (floating point) value from 0 (inclusive) to x (not inclusive).<br />  | |[[Image:bellcurve.jpg|right|200px]] Random real (floating point) value from 0 (inclusive) to x (not inclusive).<br />  | ||
<br />  | <br />  | ||
Since Arma 3 v1.55.133393 alternative syntax is added, allowing the definition of [https://en.wikipedia.org/wiki/Normal_distribution Gaussian Distribution]<ref>Technically, it is a rescaled [https://en.wikipedia.org/wiki/  | Since Arma 3 v1.55.133393 alternative syntax is added, allowing the definition of [https://en.wikipedia.org/wiki/Normal_distribution Gaussian Distribution]<ref>Technically, it is a rescaled [https://en.wikipedia.org/wiki/Bates_distribution 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.</ref> params. Uses the same method as [[setTriggerTimeout]] command. Quite useful for spawning loot for example, making more valuable items more rare ('''Alternative Syntax 1''')<br /><br />  | ||
Since Arma 3 v1.67.139663 two alternative syntaxes are available:  | Since Arma 3 v1.67.139663 two alternative syntaxes are available:  | ||
* allowing to generate semi-random number based on provided seed ('''Alternative Syntax 2''')  | * allowing to generate semi-random number based on provided seed ('''Alternative Syntax 2''')  | ||
Revision as of 13:21, 8 March 2019
Description
- Description:
 -  Random real (floating point) value from 0 (inclusive) to x (not inclusive).
Since Arma 3 v1.55.133393 alternative syntax is added, allowing the definition of Gaussian Distribution[1] params. Uses the same method as setTriggerTimeout command. Quite useful for spawning loot for example, making more valuable items more rare (Alternative Syntax 1)
Since Arma 3 v1.67.139663 two alternative syntaxes are available:- allowing to generate semi-random number based on provided seed (Alternative Syntax 2)
 - 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 (Alternative Syntax 3)
 
 - Groups:
 - Uncategorised
 
Syntax 1
Syntax 2
- Syntax:
 - random [min, mid, max] (Since Arma 3 v1.55.133393)
 - Parameters:
 - [min, mid, max]: Array
 - min: Number
 - mid: Number
 - max: Number
 - Return Value:
 - Number
 
Syntax 3
- Syntax:
 - seed random x (Since Arma 3 v1.67.139663)
 - Parameters:
 - seed: Number
 - x: Number
 - Return Value:
 - Number
 
Syntax 4
- Syntax:
 - seed random [x, y] (Since Arma 3 v1.67.139663)
 - Parameters:
 - seed: Number
 - [x, y]: Array position on the Perlin noise texture
 - x: Number
 - y: Number
 - Return Value:
 - Number
 
Examples
- Example 1:
 _rNumber = random 1;- Example 2:
 _rNumber = random -10;- Example 3:
 - Generate random position inside a circle
_center getPos [_radius * sqrt random 1, random 360]; - Example 4:
 - To select random value from an array:
_array = ["apples", "pears", "bananas", "M16"]; _random = _array select floor random count _array; // since Arma 3 v1.55.133393 _random = selectRandom _array; 
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 
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.
 
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
 - Command Group: Uncategorised
 - Scripting Commands OFP 1.46
 - Scripting Commands OFP 1.96
 - Scripting Commands OFP 1.99
 - Scripting Commands ArmA
 - Command Group: Variables
 - Scripting Commands ArmA2
 - Scripting Commands Take On Helicopters
 - Scripting Commands Arma 3