233 lines
8.0 KiB
Plaintext
233 lines
8.0 KiB
Plaintext
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{{alias}}( [options] )
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Returns a readable stream for generating pseudorandom numbers on the
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interval `[1, 2147483646]`.
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In addition to standard readable stream events, the returned stream emits a
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'state' event after internally generating `siter` pseudorandom numbers,
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which is useful when wanting to deterministically capture a stream's
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underlying PRNG state.
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The underlying pseudorandom number generator (PRNG) is a linear congruential
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pseudorandom number generator (LCG) whose output is shuffled using the Bays-
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Durham algorithm. The shuffle step considerably strengthens the "randomness
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quality" of a simple LCG's output.
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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. In
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general, this generator is unsuitable for Monte Carlo simulations and
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cryptographic applications.
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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.objectMode: boolean (optional)
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Specifies whether a stream should operate in "objectMode". Default:
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false.
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options.encoding: string|null (optional)
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Specifies how Buffer objects should be decoded to strings. Default:
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null.
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options.highWaterMark: integer (optional)
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Specifies the maximum number of bytes to store in an internal buffer
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before ceasing to generate additional pseudorandom numbers.
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options.sep: string (optional)
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Separator used to join streamed data. This option is only applicable
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when a stream is not in "objectMode". Default: '\n'.
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options.iter: integer (optional)
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Number of iterations.
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options.normalized: boolean (optional)
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Boolean indicating whether to return pseudorandom numbers on the
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interval `[0,1)`.
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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 or, for arbitrary length seeds, an array-like
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object containing signed 32-bit 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 iterator has exclusive control over
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its internal state. Default: true.
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options.siter: integer (optional)
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Number of iterations after which to emit the PRNG state. Default: 1e308.
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Returns
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-------
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stream: ReadableStream
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Readable stream.
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stream.seed: Int32Array|null
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Pseudorandom number generator seed.
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stream.seedLength: integer|null
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Length of generator seed.
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stream.state: Int32Array|null
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Generator state.
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stream.stateLength: integer|null
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Length of generator state.
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stream.byteLength: integer|null
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Size (in bytes) of generator state.
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Examples
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--------
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> function fcn( chunk ) { console.log( chunk.toString() ); };
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> var opts = { 'iter': 10 };
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> var s = {{alias}}( opts );
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> var o = {{alias:@stdlib/streams/node/inspect-sink}}( fcn );
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> s.pipe( o );
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{{alias}}.factory( [options] )
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Returns a function for creating readable streams which generate pseudorandom
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numbers on the interval `[1, 2147483646]`.
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Parameters
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----------
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options.objectMode: boolean (optional)
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Specifies whether a stream should operate in "objectMode". Default:
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false.
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options.encoding: string|null (optional)
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Specifies how Buffer objects should be decoded to strings. Default:
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null.
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options.highWaterMark: integer (optional)
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Specifies the maximum number of bytes to store in an internal buffer
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before ceasing to generate additional pseudorandom numbers.
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options.sep: string (optional)
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Separator used to join streamed data. This option is only applicable
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when a stream is not in "objectMode". Default: '\n'.
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options.iter: integer (optional)
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Number of iterations.
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options.normalized: boolean (optional)
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Boolean indicating whether to return pseudorandom numbers on the
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interval `[0,1)`.
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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 or, for arbitrary length seeds, an array-like
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object containing signed 32-bit 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 iterator has exclusive control over
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its internal state. Default: true.
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options.siter: integer (optional)
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Number of iterations after which to emit the PRNG state. Default: 1e308.
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Returns
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-------
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fcn: Function
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Function for creating readable streams.
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Examples
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--------
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> var opts = { 'objectMode': true, 'highWaterMark': 64 };
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> var createStream = {{alias}}.factory( opts );
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{{alias}}.objectMode( [options] )
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Returns an "objectMode" readable stream for generating pseudorandom numbers
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on the interval `[1, 2147483646]`.
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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.encoding: string|null (optional)
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Specifies how Buffer objects should be decoded to strings. Default:
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null.
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options.highWaterMark: integer (optional)
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Specifies the maximum number of objects to store in an internal buffer
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before ceasing to generate additional pseudorandom numbers.
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options.iter: integer (optional)
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Number of iterations.
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options.normalized: boolean (optional)
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Boolean indicating whether to return pseudorandom numbers on the
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interval `[0,1)`.
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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 or, for arbitrary length seeds, an array-like
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object containing signed 32-bit 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 iterator has exclusive control over
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its internal state. Default: true.
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options.siter: integer (optional)
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Number of iterations after which to emit the PRNG state. Default: 1e308.
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Returns
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-------
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stream: ReadableStream
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Readable stream operating in "objectMode".
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stream.seed: Int32Array|null
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Pseudorandom number generator seed.
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stream.seedLength: integer|null
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Length of generator seed.
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stream.state: Int32Array|null
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Generator state.
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stream.stateLength: integer|null
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Length of generator state.
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stream.byteLength: integer|null
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Size (in bytes) of generator state.
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Examples
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--------
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> function fcn( v ) { console.log( v ); };
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> var opts = { 'iter': 10 };
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> var s = {{alias}}.objectMode( opts );
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> var o = {{alias:@stdlib/streams/node/inspect-sink}}.objectMode( fcn );
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> s.pipe( o );
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See Also
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--------
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