random: Difference between revisions

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m (Reverted edits by Heecf..... (talk) to last revision by Str)
(Added probability clarification to round and floor.)
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* 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.  
* 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.<br>To return a whole number use either '''[[round]]''', '''[[ceil]]''' or '''[[floor]]''' together with '''random''':<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''':<br>
  x=round(random 5) will return 0,1,2,3,4 or 5.
  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.
  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)
  x=ceil(random 5) will return 0,1,2,3,4 or 5. (0 is very unlikely, but possible, as ceil 0 is 0)
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Revision as of 12:09, 28 December 2012

Hover & click on the images for description

Description

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

Syntax

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

Examples

Example 1:
_rNumber = random 1

Additional Information

See also:
Math Commands

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

  • 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)

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