Kumaraswamy's double bounded distributed pseudorandom numbers.
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[Kumaraswamy’s double bounded][kumaraswamy] distributed pseudorandom numbers.
bash
npm install @stdlib/random-base-kumaraswamy
script
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 kumaraswamy = require( '@stdlib/random-base-kumaraswamy' );
a
(first shape parameter) and b
(second shape parameter).javascript
var r = kumaraswamy( 2.0, 5.0 );
// returns <number>
a <= 0
or b <= 0
, the function returns NaN
.javascript
var r = kumaraswamy( 2.0, -2.0 );
// returns NaN
r = kumaraswamy( -2.0, 2.0 );
// returns NaN
a
or b
is NaN
, the function returns NaN
.javascript
var r = kumaraswamy( NaN, 5.0 );
// returns NaN
r = kumaraswamy( 2.0, NaN );
// returns NaN
javascript
var rand = kumaraswamy.factory();
var r = rand( 1.5, 1.5 );
// returns <number>
a
and b
, the returned generator returns random variates from the specified distribution.javascript
// Draw from Kumaraswamy( 1.5, 1.5 ) distribution:
var rand = kumaraswamy.factory( 1.5, 1.5 );
var r = rand();
// returns <number>
r = rand();
// returns <number>
a
and b
, the returned generator requires that both parameters be provided at each invocation.javascript
var rand = kumaraswamy.factory();
var r = rand( 1.0, 1.0 );
// returns <number>
r = rand( 3.14, 2.25 );
// returns <number>
options
:[0,1)
. If provided, the function ignores both the state
and seed
options. In order to seed the returned pseudorandom number generator, 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. Setting this option to true
ensures that a returned generator has exclusive control over its internal state. Default: true
.prng
option.javascript
var minstd = require( '@stdlib/random-base-minstd' );
var rand = kumaraswamy.factory({
'prng': minstd.normalized
});
var r = rand( 2.0, 3.0 );
// returns <number>
seed
option.javascript
var rand1 = kumaraswamy.factory({
'seed': 12345
});
var r1 = rand1( 2.0, 3.0 );
// returns <number>
var rand2 = kumaraswamy.factory( 2.0, 3.0, {
'seed': 12345
});
var r2 = rand2();
// returns <number>
var bool = ( r1 === r2 );
// returns true
state
option.javascript
var rand;
var bool;
var r;
var i;
// Generate pseudorandom numbers, thus progressing the generator state:
for ( i = 0; i < 1000; i++ ) {
r = kumaraswamy( 2.0, 3.0 );
}
// Create a new PRNG initialized to the current state of `kumaraswamy`:
rand = kumaraswamy.factory({
'state': kumaraswamy.state
});
// Test that the generated pseudorandom numbers are the same:
bool = ( rand( 2.0, 3.0 ) === kumaraswamy( 2.0, 3.0 ) );
// returns true
javascript
var str = kumaraswamy.NAME;
// returns 'kumaraswamy'
javascript
var prng = kumaraswamy.PRNG;
// returns <Function>
kumaraswamy()
.javascript
var rand;
var r;
var i;
// Generate pseudorandom values...
for ( i = 0; i < 100; i++ ) {
r = kumaraswamy( 2.0, 2.0 );
}
// Generate the same pseudorandom values...
rand = kumaraswamy.factory( 2.0, 2.0, {
'seed': kumaraswamy.seed
});
for ( i = 0; i < 100; i++ ) {
r = rand();
}
null
.javascript
var rand = kumaraswamy.factory({
'prng': Math.random
});
var seed = rand.seed;
// returns null
javascript
var len = kumaraswamy.seedLength;
// returns <number>
null
.javascript
var rand = kumaraswamy.factory({
'prng': Math.random
});
var len = rand.seedLength;
// returns null
javascript
var r = kumaraswamy( 2.0, 5.0 );
// returns <number>
r = kumaraswamy( 2.0, 5.0 );
// returns <number>
// ...
// Get a copy of the current state:
var state = kumaraswamy.state;
// returns <Uint32Array>
r = kumaraswamy( 2.0, 5.0 );
// returns <number>
r = kumaraswamy( 2.0, 5.0 );
// returns <number>
// Reset the state:
kumaraswamy.state = state;
// Replay the last two pseudorandom numbers:
r = kumaraswamy( 2.0, 5.0 );
// returns <number>
r = kumaraswamy( 2.0, 5.0 );
// returns <number>
// ...
null
.javascript
var rand = kumaraswamy.factory({
'prng': Math.random
});
var state = rand.state;
// returns null
javascript
var len = kumaraswamy.stateLength;
// returns <number>
null
.javascript
var rand = kumaraswamy.factory({
'prng': Math.random
});
var len = rand.stateLength;
// returns null
javascript
var sz = kumaraswamy.byteLength;
// returns <number>
null
.javascript
var rand = kumaraswamy.factory({
'prng': Math.random
});
var sz = rand.byteLength;
// returns null
javascript
var o = kumaraswamy.toJSON();
// returns { 'type': 'PRNG', 'name': '...', 'state': {...}, 'params': [] }
null
.javascript
var rand = kumaraswamy.factory({
'prng': Math.random
});
var o = rand.toJSON();
// returns null
javascript
var kumaraswamy = require( '@stdlib/random-base-kumaraswamy' );
var seed;
var rand;
var i;
// Generate pseudorandom numbers...
for ( i = 0; i < 100; i++ ) {
console.log( kumaraswamy( 2.0, 2.0 ) );
}
// Create a new pseudorandom number generator...
seed = 1234;
rand = kumaraswamy.factory( 6.0, 2.0, {
'seed': seed
});
for ( i = 0; i < 100; i++ ) {
console.log( rand() );
}
// Create another pseudorandom number generator using a previous seed...
rand = kumaraswamy.factory( 2.0, 2.0, {
'seed': kumaraswamy.seed
});
for ( i = 0; i < 100; i++ ) {
console.log( rand() );
}