time-to-botec/squiggle/node_modules/@stdlib/math/iter/sequences/factorials

iterFactorialsSeq

Create an iterator which generates a sequence of factorials.

The factorial function may be defined as the product

or according to the recurrence relation

Following the convention for an empty product, in all definitions,

Usage

var iterFactorialsSeq = require( '@stdlib/math/iter/sequences/factorials' );

iterFactorialsSeq( [options] )

Returns an iterator which generates a sequence of factorials.

var it = iterFactorialsSeq();
// returns <Object>

var v = it.next().value;
// returns 1

v = it.next().value;
// returns 1

v = it.next().value;
// returns 2

v = it.next().value;
// returns 6

v = it.next().value;
// returns 24

// ...

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 a done property having a boolean 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.

The function supports the following options:

• iter: number of iterations. Default: 1e308.

By default, the function returns an infinite iterator (i.e., an iterator which never ends). To limit the number of iterations, set the iter option.

var opts = {
    'iter': 2
};
var it = iterFactorialsSeq( opts );
// returns <Object>

var v = it.next().value;
// returns 1

v = it.next().value;
// returns 1

var bool = it.next().done;
// returns true

Notes

• If an environment supports Symbol.iterator, the returned iterator is iterable.

Examples

var iterFactorialsSeq = require( '@stdlib/math/iter/sequences/factorials' );

// Create an iterator:
var opts = {
    'iter': 100
};
var it = iterFactorialsSeq( opts );

// Perform manual iteration...
var v;
while ( true ) {
    v = it.next();
    if ( v.done ) {
        break;
    }
    console.log( v.value );
}