Difference between revisions of "random"

From Bohemia Interactive Community
Jump to navigation Jump to search
m (Text replacement - " <!-- (DIS)?CONTINUE Notes -->" to "")
m (formatting)
Line 1: Line 1:
 
{{RV|type=command
 
{{RV|type=command
  
| ofp
+
|game1= ofp
  
|1.00
+
|version1= 1.00
 +
 
 +
|game2= ofpe
 +
 
 +
|version2= 1.00
 +
 
 +
|game3= arma1
 +
 
 +
|version3= 1.00
 +
 
 +
|game4= arma2
 +
 
 +
|version4= 1.00
 +
 
 +
|game5= arma2oa
 +
 
 +
|version5= 1.51
 +
 
 +
|game6= tkoh
 +
 
 +
|version6= 1.00
 +
 
 +
|game7= arma3
 +
 
 +
|version7= 0.50
  
 
|gr1= Math
 
|gr1= Math
  
|[[Image:bellcurve.jpg|right|200px]] Random real (floating point) value from 0 (inclusive) to x (not inclusive).<br>
+
|descr= [[Image:bellcurve.jpg|right|200px]] Random real (floating point) value from 0 (inclusive) to x (not inclusive).<br>
 
<br>
 
<br>
 
Since Arma 3 v1.56 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 v1.56 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>
Line 14: Line 38:
 
* generating pseudo-random [https://en.wikipedia.org/wiki/Perlin_noise 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''')
 
* generating pseudo-random [https://en.wikipedia.org/wiki/Perlin_noise 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''')
  
| [[random]] x
+
|s1= [[random]] x
  
 
|p1= x: [[Number]]
 
|p1= x: [[Number]]
  
| [[Number]]
+
|r1= [[Number]]
 +
 
 +
|s2= [[random]] [min, mid, max] {{Since|arma3|1.56|y}}
  
|s2= [[random]] [min, mid, max] {{Since|arma3|1.55.133393|y}}
 
 
|p21= [min, mid, max]: [[Array]]
 
|p21= [min, mid, max]: [[Array]]
 +
 
|p22= min: [[Number]]
 
|p22= min: [[Number]]
 +
 
|p23= mid: [[Number]]
 
|p23= mid: [[Number]]
 +
 
|p24= max: [[Number]]
 
|p24= max: [[Number]]
 +
 
|r2= [[Number]]
 
|r2= [[Number]]
  
|s3= seed [[random]] x {{Since|arma3|1.67.139663|y}}
+
|s3= seed [[random]] x {{Since|arma3|1.68|y}}
 +
 
 
|p41= seed: [[Number]]
 
|p41= seed: [[Number]]
 +
 
|p42= x: [[Number]]
 
|p42= x: [[Number]]
|r3= [[Number]] - value from 0 to x
 
  
|s4= seed [[random]] [x, y] {{Since|arma3|1.67.139663|y}}
+
|r3= [[Number]] - Value from 0 to x
 +
 
 +
|s4= seed [[random]] [x, y] {{Since|arma3|1.68|y}}
 +
 
 
|p61= seed: [[Number]]
 
|p61= seed: [[Number]]
|p62= [x, y]: [[Array]] position on the [https://en.wikipedia.org/wiki/Perlin_noise Perlin noise texture]
+
 
 +
|p62= [x, y]: [[Array]] - Position on the [https://en.wikipedia.org/wiki/Perlin_noise Perlin noise texture]
 +
 
 
|p63= x: [[Number]]
 
|p63= x: [[Number]]
 +
 
|p64= y: [[Number]]
 
|p64= y: [[Number]]
|r4= [[Number]] - value from 0 to 1
+
 
 +
|r4= [[Number]] - Value from 0 to 1
 
   
 
   
 
|x1= <code>_rNumber = [[random]] 1;</code>
 
|x1= <code>_rNumber = [[random]] 1;</code>
Line 49: Line 86:
 
<code>_array = ["apples", "pears", "bananas", "M16"];
 
<code>_array = ["apples", "pears", "bananas", "M16"];
 
_random = _array [[select]] [[floor]] [[random]] [[count]] _array;
 
_random = _array [[select]] [[floor]] [[random]] [[count]] _array;
{{cc|{{Since|arma3|1.55.133393}}}}
+
{{cc|{{Since|arma3|1.56}}}}
 
_random = [[selectRandom]] _array;</code>
 
_random = [[selectRandom]] _array;</code>
  
Line 55: Line 92:
 
}}
 
}}
  
 
[[Category:Scripting Commands|{{uc:{{PAGENAME}}}}]]
 
{{GameCategory|arma1|Scripting Commands}}
 
{{GameCategory|arma2|Scripting Commands}}
 
{{GameCategory|arma3|Scripting Commands}}
 
{{GameCategory|tkoh|Scripting Commands}}
 
  
 
<dl class="command_description">
 
<dl class="command_description">

Revision as of 10:11, 29 May 2021

Hover & click on the images for description

Description

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


Since Arma 3 v1.56 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 v1.68 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:
Math

Syntax 1

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

Syntax 2

Syntax:
random [min, mid, max] Template:Since
Parameters:
[min, mid, max]: Array
min: Number
mid: Number
max: Number
Return Value:
Number

Syntax 3

Syntax:
seed random x Template:Since
Parameters:
seed: Number
x: Number
Return Value:
Number - Value from 0 to x

Syntax 4

Syntax:
seed random [x, y] Template:Since
Parameters:
seed: Number
[x, y]: Array - Position on the Perlin noise texture
x: Number
y: Number
Return Value:
Number - Value from 0 to 1

Examples

Example 1:
_rNumber = random 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:
To select random value from an array: _array = ["apples", "pears", "bananas", "M16"]; _random = _array select floor random count _array; // Template:Since _random = selectRandom _array;

Additional Information

See also:
selectRandomselectRandomWeighted

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.
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)
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%
  1. 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.