time-to-botec/js/node_modules/@stdlib/math/iter/ops/subtract

iterSubtract

Create an iterator which performs element-wise subtraction of two or more iterators.

Usage

var iterSubtract = require( '@stdlib/math/iter/ops/subtract' );

iterSubtract( iter0, ...iterator )

Returns an iterator which performs element-wise subtraction of two or more iterators.

var array2iterator = require( '@stdlib/array/to-iterator' );

var it1 = array2iterator( [ 1.0, 5.0 ] );
var it2 = array2iterator( [ 3.0, 4.0 ] );

var it = iterSubtract( it1, it2 );
// returns <Object>

var v = it.next().value;
// returns -2.0

v = it.next().value;
// returns 1.0

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 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.

If provided a numeric value as an iterator argument, the value is broadcast as an infinite iterator which always returns the provided value.

var array2iterator = require( '@stdlib/array/to-iterator' );

var arr = array2iterator( [ 1.0, 2.0 ] );

var it = iterSubtract( arr, 4.0 );
// returns <Object>

var v = it.next().value;
// returns -3.0

v = it.next().value;
// returns -2.0

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

Notes

• If an iterated value is non-numeric (including NaN), the returned iterator returns NaN. If non-numeric iterated values are possible, you are advised to provide an iterator which type checks and handles non-numeric values accordingly.
• The length of the returned iterator is equal to the length of the shortest provided iterator. In other words, the returned iterator ends once one of the provided iterators ends.
• If an environment supports Symbol.iterator and provided iterators are iterable, the returned iterator is iterable.

Examples

var iterSineWave = require( '@stdlib/simulate/iter/sine-wave' );
var iterSubtract = require( '@stdlib/math/iter/ops/subtract' );

// Create an iterator which generates a sine wave:
var sine1 = iterSineWave({
    'period': 50,
    'offset': 0,
    'iter': 100
});

// Create another iterator which generates a higher frequency sine wave:
var sine2 = iterSineWave({
    'period': 10,
    'offset': 0,
    'iter': 100
});

// Create an iterator which subtracts the two waveforms:
var it = iterSubtract( sine1, sine2 );

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