# iterBeta > Create an [iterator][mdn-iterator-protocol] which iteratively evaluates the [beta function][@stdlib/math/base/special/beta].
## Usage ```javascript var iterBeta = require( '@stdlib/math/iter/special/beta' ); ``` #### iterBeta( x, y ) Returns an [iterator][mdn-iterator-protocol] which iteratively evaluates the [beta function][@stdlib/math/base/special/beta]. ```javascript var array2iterator = require( '@stdlib/array/to-iterator' ); var x = array2iterator( [ 1.0, 5.0, 4.0 ] ); var y = array2iterator( [ 1.0, 0.2, 1.0 ] ); var it = iterBeta( x, y ); // returns var r = it.next().value; // returns 1.0 r = it.next().value; // returns ~3.382 r = it.next().value; // returns 0.25 // ... ``` The returned [iterator][mdn-iterator-protocol] protocol-compliant object has the following properties: - **next**: function which returns an [iterator][mdn-iterator-protocol] protocol-compliant object containing the next iterated value (if one exists) assigned to a `value` property and a `done` property having a `boolean` value indicating whether the iterator is finished. - **return**: function which closes an [iterator][mdn-iterator-protocol] and returns a single (optional) argument in an [iterator][mdn-iterator-protocol] protocol-compliant object. If provided a numeric value as an [`iterator`][mdn-iterator-protocol] argument, the value is broadcast as an **infinite** [iterator][mdn-iterator-protocol] which **always** returns the provided value. ```javascript var array2iterator = require( '@stdlib/array/to-iterator' ); var x = array2iterator( [ 1.0, 5.0 ] ); var it = iterBeta( x, 2.0 ); // returns var v = it.next().value; // returns 0.5 v = it.next().value; // returns ~0.0333 var bool = it.next().done; // returns true ```
## Notes - If an iterated value is non-numeric (including `NaN`), the returned [iterator][mdn-iterator-protocol] returns `NaN`. If non-numeric iterated values are possible, you are advised to provide an [`iterator`][mdn-iterator-protocol] which type checks and handles non-numeric values accordingly. - The length of the returned [iterator][mdn-iterator-protocol] is equal to the length of the shortest provided [iterator][mdn-iterator-protocol]. In other words, the returned [iterator][mdn-iterator-protocol] ends once **one** of the provided [iterators][mdn-iterator-protocol] ends. - If an environment supports `Symbol.iterator` **and** a provided [iterator][mdn-iterator-protocol] is iterable, the returned [iterator][mdn-iterator-protocol] is iterable.
## Examples ```javascript var uniform = require( '@stdlib/random/iter/uniform' ); var iterBeta = require( '@stdlib/math/iter/special/beta' ); // Create seeded iterators for generating pseudorandom numbers: var x = uniform( 0.0, 2.0, { 'seed': 1234, 'iter': 10 }); var y = uniform( 0.0, 2.0, { 'seed': 4567, 'iter': 10 }); // Create an iterator which consumes the pseudorandom number iterators: var it = iterBeta( x, y ); // Perform manual iteration... var r; while ( true ) { r = it.next(); if ( r.done ) { break; } console.log( r.value ); } ```