Create a readable stream for generating pseudorandom numbers drawn from a Cauchy distribution.
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Create a [readable stream][readable-stream] for generating pseudorandom numbers drawn from a [Cauchy][cauchy] distribution.
bash
npm install @stdlib/random-streams-cauchyscript tag without installation and bundlers, use the [ES Module][es-module] available on the [esm][esm-url] branch (see [README][esm-readme]).deno][deno-url] branch (see [README][deno-readme] for usage intructions).umd][umd-url] branch (see [README][umd-readme]).javascript
var randomStream = require( '@stdlib/random-streams-cauchy' );x0 (location) and gamma (scale).javascript
var inspectStream = require( '@stdlib/streams-node-inspect-sink' );
var iStream;
var stream;
function log( chunk, idx ) {
console.log( chunk.toString() );
if ( idx === 10 ) {
stream.destroy();
}
}
stream = randomStream( -2.0, 2.0 );
iStream = inspectStream( log );
stream.pipe( iStream );options:false.Buffer objects should be decoded to strings. Default: null.'\n'.[0,1). If provided, the function ignores both the state and seed options. In order to seed the returned pseudorandom number generator stream, one must seed the provided prng (assuming the provided prng is seedable).Uint32Array][@stdlib/array/uint32] containing pseudorandom number generator state. If provided, the function ignores the seed option.boolean indicating whether to copy a provided pseudorandom number generator state. Setting this option to false allows sharing state between two or more pseudorandom number generators and/or streams. Setting this option to true ensures that a stream generator has exclusive control over its internal state. Default: true.1e308.options,javascript
var opts = {
'objectMode': true,
'encoding': 'utf8',
'highWaterMark': 64
};
var stream = randomStream( 0.0, 2.0, opts );iter option.javascript
var inspectStream = require( '@stdlib/streams-node-inspect-sink' );
function log( chunk ) {
console.log( chunk.toString() );
}
var opts = {
'iter': 10
};
var stream = randomStream( 0.0, 1.0, opts );
var iStream = inspectStream( log );
stream.pipe( iStream );sep option.javascript
var inspectStream = require( '@stdlib/streams-node-inspect-sink' );
function log( chunk ) {
console.log( chunk.toString() );
}
var opts = {
'iter': 10,
'sep': ','
};
var stream = randomStream( 2.0, 1.0, opts );
var iStream = inspectStream( log );
stream.pipe( iStream );seed option.javascript
var inspectStream = require( '@stdlib/streams-node-inspect-sink' );
function log( v ) {
console.log( v );
}
var opts = {
'objectMode': true,
'iter': 10,
'seed': 1234
};
var stream = randomStream( 2.0, 1.0, opts );
opts = {
'objectMode': true
};
var iStream = inspectStream( opts, log );
stream.pipe( iStream );state option.javascript
var inspectStream = require( '@stdlib/streams-node-inspect-sink' );
function log( v ) {
console.log( v );
}
var opts1 = {
'objectMode': true,
'iter': 10
};
var stream = randomStream( 2.0, 2.0, opts1 );
var opts2 = {
'objectMode': true
};
var iStream = inspectStream( opts2, log );
// Stream pseudorandom numbers, thus progressing the underlying generator state:
stream.pipe( iStream );
// Create a new PRNG stream initialized to the last state of the previous stream:
var opts3 = {
'objectMode': true,
'iter': 10,
'state': stream.state
};
stream = randomStream( 2.0, 2.0, opts3 );
iStream = inspectStream( opts2, log );
// Stream pseudorandom numbers starting from the last state of the previous stream:
stream.pipe( iStream );javascript
var stream = randomStream( 2.0, 2.0 );
var prng = stream.PRNG;
// returns <Function>javascript
var stream = randomStream( 2.0, 2.0 );
var seed = stream.seed;
// returns <Uint32Array>null.javascript
var minstd = require( '@stdlib/random-base-minstd-shuffle' ).normalized;
var stream = randomStream( 2.0, 2.0, {
'prng': minstd
});
var seed = stream.seed;
// returns nulljavascript
var stream = randomStream( 2.0, 2.0 );
var len = stream.seedLength;
// returns <number>null.javascript
var minstd = require( '@stdlib/random-base-minstd-shuffle' ).normalized;
var stream = randomStream( 2.0, 2.0, {
'prng': minstd
});
var len = stream.seedLength;
// returns nulljavascript
var stream = randomStream( 2.0, 2.0 );
var state = stream.state;
// returns <Uint32Array>null.javascript
var minstd = require( '@stdlib/random-base-minstd-shuffle' ).normalized;
var stream = randomStream( 2.0, 2.0, {
'prng': minstd
});
var state = stream.state;
// returns nulljavascript
var stream = randomStream( 2.0, 2.0 );
var len = stream.stateLength;
// returns <number>null.javascript
var minstd = require( '@stdlib/random-base-minstd-shuffle' ).normalized;
var stream = randomStream( 2.0, 2.0, {
'prng': minstd
});
var len = stream.stateLength;
// returns nulljavascript
var stream = randomStream( 2.0, 2.0 );
var sz = stream.byteLength;
// returns <number>null.javascript
var minstd = require( '@stdlib/random-base-minstd-shuffle' ).normalized;
var stream = randomStream( 2.0, 2.0, {
'prng': minstd
});
var sz = stream.byteLength;
// returns nullfunction for creating [readable streams][readable-stream] which generate pseudorandom numbers drawn from a [Cauchy][cauchy] distribution.javascript
var opts = {
'objectMode': true,
'encoding': 'utf8',
'highWaterMark': 64
};
var createStream = randomStream.factory( opts );javascript
var createStream = randomStream.factory( 2.0, 2.0 );
var stream1 = createStream();
var stream2 = createStream();
// ...javascript
var createStream = randomStream.factory();
var stream1 = createStream( 2.0, 2.0 );
var stream2 = createStream( 2.0, 2.0 );
// ...options as randomStream().
javascript
var inspectStream = require( '@stdlib/streams-node-inspect-sink' );
function log( v ) {
console.log( v );
}
var opts = {
'iter': 10
};
var stream = randomStream.objectMode( 2.0, 2.0, opts );
opts = {
'objectMode': true
};
var iStream = inspectStream( opts, log );
stream.pipe( iStream );options as randomStream(); however, the method will always override the [objectMode][object-mode] option in options.siter pseudorandom numbers.javascript
var opts = {
'siter': 10 // emit the PRNG state every 10 pseudorandom numbers
};
var stream = randomStream( 2.0, 2.0, opts );
stream.on( 'state', onState );
function onState( state ) {
// Do something with the emitted state, such as save to file...
}siter option in conjunction with a state event listener. Attempting to capture the underlying PRNG state after reading generated numbers is not likely to give expected results, as internal stream buffering will mean more values have been generated than have been read. Thus, the state returned by the state property will likely reflect a future PRNG state from the perspective of downstream consumers.javascript
var inspectStream = require( '@stdlib/streams-node-inspect-sink' );
var randomStream = require( '@stdlib/random-streams-cauchy' );
function log( v ) {
console.log( v.toString() );
}
var opts = {
'objectMode': true,
'iter': 10
};
var stream = randomStream( 2.0, 2.0, opts );
opts = {
'objectMode': true
};
var iStream = inspectStream( opts, log );
stream.pipe( iStream );bash
npm install -g @stdlib/random-streams-cauchy-clitext
Usage: random-cauchy [options] <x0> <gamma>
Options:
-h, --help Print this message.
-V, --version Print the package version.
--sep sep Separator used to join streamed data. Default: '\n'.
-n, --iter iterations Number of pseudorandom numbers.
--seed seed Pseudorandom number generator seed.
--state filepath Path to a file containing the pseudorandom number
generator state.
--snapshot filepath Output file path for saving the pseudorandom number
generator state upon exit.bash
$ random-cauchy 0.0 1.0 -n 10 --seed 1234
