189 lines
3.9 KiB
Plaintext
189 lines
3.9 KiB
Plaintext
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{{alias}}()
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Returns a pseudorandom integer on the interval `[1, 2147483646]`.
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This pseudorandom number generator (PRNG) is a linear congruential
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pseudorandom number generator (LCG) based on Park and Miller.
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The generator has a period of approximately `2.1e9`.
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An LCG is fast and uses little memory. On the other hand, because the
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generator is a simple LCG, the generator has recognized shortcomings. By
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today's PRNG standards, the generator's period is relatively short. More
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importantly, the "randomness quality" of the generator's output is lacking.
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These defects make the generator unsuitable, for example, in Monte Carlo
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simulations and in cryptographic applications.
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Returns
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-------
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r: integer
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Pseudorandom number.
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Examples
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--------
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> var r = {{alias}}();
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{{alias}}.normalized()
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Returns a pseudorandom number on the interval `[0,1)`.
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Returns
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-------
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r: number
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Pseudorandom number.
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Examples
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--------
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> var r = {{alias}}.normalized();
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{{alias}}.factory( [options] )
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Returns a linear congruential pseudorandom number generator (LCG).
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Parameters
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----------
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options: Object (optional)
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Options.
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options.seed: integer|ArrayLikeObject<integer> (optional)
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Pseudorandom number generator seed. The seed may be either a positive
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signed 32-bit integer on the interval `[1, 2147483646]` or, for
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arbitrary length seeds, an array-like object containing signed 32-bit
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integers.
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options.state: Int32Array (optional)
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Pseudorandom number generator state. If provided, the `seed` option is
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ignored.
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options.copy: boolean (optional)
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Boolean indicating whether to copy a provided pseudorandom number
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generator state. Setting this option to `false` allows sharing state
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between two or more pseudorandom number generators. Setting this option
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to `true` ensures that a returned generator has exclusive control over
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its internal state. Default: true.
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Returns
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-------
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rand: Function
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Pseudorandom number generator (PRNG).
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Examples
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--------
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// Basic usage:
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> var rand = {{alias}}.factory();
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> r = rand();
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> r = rand();
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// Provide a seed:
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> rand = {{alias}}.factory( { 'seed': 1234 } );
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> r = rand()
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20739838
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{{alias}}.NAME
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Generator name.
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Examples
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--------
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> var str = {{alias}}.NAME
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'minstd'
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{{alias}}.MIN
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Minimum possible value.
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Examples
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--------
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> var v = {{alias}}.MIN
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1
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{{alias}}.MAX
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Maximum possible value.
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Examples
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--------
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> var v = {{alias}}.MAX
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2147483646
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{{alias}}.seed
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Pseudorandom number generator seed.
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Examples
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--------
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> var seed = {{alias}}.seed;
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{{alias}}.seedLength
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Length of generator seed.
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Examples
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--------
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> var len = {{alias}}.seedLength;
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{{alias}}.state
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Generator state.
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Examples
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--------
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> var r = {{alias}}()
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<number>
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> r = {{alias}}()
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<number>
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> r = {{alias}}()
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<number>
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// Get the current state:
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> var state = {{alias}}.state
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<Int32Array>
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> r = {{alias}}()
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<number>
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> r = {{alias}}()
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<number>
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// Set the state:
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> {{alias}}.state = state;
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// Replay the last two pseudorandom numbers:
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> r = {{alias}}()
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<number>
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> r = {{alias}}()
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<number>
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{{alias}}.stateLength
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Length of generator state.
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Examples
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--------
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> var len = {{alias}}.stateLength;
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{{alias}}.byteLength
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Size (in bytes) of generator state.
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Examples
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--------
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> var sz = {{alias}}.byteLength;
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{{alias}}.toJSON()
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Serializes the pseudorandom number generator as a JSON object.
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Returns
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-------
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out: Object
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JSON representation.
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Examples
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--------
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> var o = {{alias}}.toJSON()
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{ 'type': 'PRNG', 'name': '...', 'state': {...}, 'params': [] }
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See Also
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--------
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