Difference between revisions of "API:RNG::next"

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{{DISPLAYTITLE:RNG::next()}}
 
{{DISPLAYTITLE:RNG::next()}}
  
The <tt>'''RNG::next()'''</tt> method returns a random floating-point number in the range <tt>[0,1)</tt>.
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The <tt>'''RNG::next()'''</tt> method generates a random floating-point number in the range <tt>[0,1)</tt>.
  
 
=== Usage ===
 
=== Usage ===
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=== Description ===
 
=== Description ===
  
<tt>'''RNG::next()'''</tt> generates a pseudorandom floating-point value greater than or equal to 0 but less than 1 and returns the value so generated.  The value this function returns is entirely determined by the current state of the <tt>RNG</tt> instance before the call (see <tt>[[API:RNG::state|RNG::state]]</tt>).  After calling this function, the state is advanced so a different value will be generated next time.  If you save the state before <tt>RNG.next()</tt>, then restore it afterwards and call <tt>RNG.next()</tt> again, the same value will be generated.
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<tt>'''RNG::next()'''</tt> generates a pseudorandom floating-point number greater than or equal to 0 but less than 1 and returns the value generated.  The number generated is entirely determined by the current state of the <tt>RNG</tt> instance before the call (see <tt>[[API:RNG::state|RNG::state]]</tt>).  After calling this function, the state is advanced so a different value will be generated next time.  Therefore if you save the RNG's state before calling <tt>RNG.next()</tt>, then restore it afterwards and call <tt>RNG.next()</tt> again, the same value will be returned.
  
=== Examples ===
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=== Parameters ===
  
==== Shuffle items in an array ====
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This method has no parameters.
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=== Return Value ===
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A floating-point number in the range <tt>[0,1)</tt>.
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== Examples ==
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=== Shuffle an array ===
  
 
  let items = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ]
 
  let items = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ]
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  let rnGen = new RNG();
 
  let rnGen = new RNG();
 
  for (let i = items.length - 1; i > 0; --i) {
 
  for (let i = items.length - 1; i > 0; --i) {
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     items[j] = orig_i;
 
     items[j] = orig_i;
 
  }
 
  }
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== See Also ==
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<tt>
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* [[API:RNG::state|RNG::state]]
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</tt>
  
 
[[Category:Sphere 2 API]]
 
[[Category:Sphere 2 API]]

Latest revision as of 03:53, 10 August 2017


The RNG::next() method generates a random floating-point number in the range [0,1).

Usage

number = rng_object.next();

API Information

Description

RNG::next() generates a pseudorandom floating-point number greater than or equal to 0 but less than 1 and returns the value generated. The number generated is entirely determined by the current state of the RNG instance before the call (see RNG::state). After calling this function, the state is advanced so a different value will be generated next time. Therefore if you save the RNG's state before calling RNG.next(), then restore it afterwards and call RNG.next() again, the same value will be returned.

Parameters

This method has no parameters.

Return Value

A floating-point number in the range [0,1).

Examples

Shuffle an array

let items = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ]

let rnGen = new RNG();
for (let i = items.length - 1; i > 0; --i) {
    let j = Math.floor(rnGen.next() * (i + 1));  // discrete [0,i]
    let orig_i = items[i];
    items[i] = items[j];
    items[j] = orig_i;
}

See Also