@stdlib/iter-intersection
v0.2.2
Published
Create an iterator which returns the intersection of two or more iterators.
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iterIntersection
Create an iterator which returns the intersection of two or more iterators.
Installation
npm install @stdlib/iter-intersection
Usage
var iterIntersection = require( '@stdlib/iter-intersection' );
iterIntersection( iter0, ...iterator )
Returns an iterator which returns the intersection of two or more iterators.
var array2iterator = require( '@stdlib/array-to-iterator' );
var it1 = array2iterator( [ 2, 1, 1, 2, 4 ] );
var it2 = array2iterator( [ 3, 4, 3 ] );
var it = iterIntersection( it1, it2 );
// returns <Object>
var v = it.next().value;
// returns 4
var bool = it.next().done;
// returns true
The returned iterator protocol-compliant object has the following properties:
- next: function which returns an iterator protocol-compliant object containing the next iterated value (if one exists) assigned to a
value
property and adone
property having aboolean
value indicating whether the iterator is finished. - return: function which closes an iterator and returns a single (optional) argument in an iterator protocol-compliant object.
Notes
- Value "uniqueness" is determined according to strict equality.
- A returned iterator internally buffers unique values and, thus, has
O(N)
memory requirements, whereN
is the length of the first iterator. - Do not provide iterators having infinite length.
- If an environment supports
Symbol.iterator
and all provided iterators are iterable, the returned iterator is iterable.
Examples
var discreteUniform = require( '@stdlib/random-iter-discrete-uniform' );
var iterIntersection = require( '@stdlib/iter-intersection' );
// Create seeded iterators which can generate 1000 pseudorandom numbers:
var rand1 = discreteUniform( 1, 10, {
'seed': 1234,
'iter': 1000
});
var rand2 = discreteUniform( 6, 15, {
'seed': 1234,
'iter': 1000
});
// Create an iterator which returns the intersection of the seeded iterators:
var it = iterIntersection( rand1, rand2 );
// Perform manual iteration...
var v;
while ( true ) {
v = it.next();
if ( v.done ) {
break;
}
console.log( v.value );
}
See Also
@stdlib/iter-intersection-by-hash
: create an iterator which returns the intersection of two or more iterators according to a hash function.@stdlib/iter-union
: create an iterator which returns the union of two or more iterators.@stdlib/iter-unique
: create an iterator which returns unique values.
Notice
This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.
Community
License
See LICENSE.
Copyright
Copyright © 2016-2024. The Stdlib Authors.