@stdlib/array-complex128

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Complex128Array

128-bit complex number array.

Installation

npm install @stdlib/array-complex128

Usage

var Complex128Array = require( '@stdlib/array-complex128' );

Complex128Array()

Creates a 128-bit complex number array.

var arr = new Complex128Array();
// returns <Complex128Array>

Complex128Array( length )

Creates a 128-bit complex number array having a specified length.

var arr = new Complex128Array( 10 );
// returns <Complex128Array>

var len = arr.length;
// returns 10

Complex128Array( complexarray )

Creates a 128-bit complex number array from another complex number array.

var arr1 = new Complex128Array( [ 1.0, -1.0, 2.0, -2.0 ] ); // [ re, im, re, im ]
// returns <Complex128Array>

var arr2 = new Complex128Array( arr1 );
// returns <Complex128Array>

var len = arr2.length;
// returns 2

Complex128Array( typedarray )

Creates a 128-bit complex number array from a typed array containing interleaved real and imaginary components.

var Float64Array = require( '@stdlib/array-float64' );

var buf = new Float64Array( [ 1.0, -1.0, 2.0, -2.0 ] ); // [ re, im, re, im ]
// returns <Float64Array>[ 1.0, -1.0, 2.0, -2.0 ]

var arr = new Complex128Array( buf );
// returns <Complex128Array>

var len = arr.length;
// returns 2

Complex128Array( obj )

Creates a 128-bit complex number array from an array-like object or iterable.

var Complex128 = require( '@stdlib/complex-float64' );

// From an array of interleaved real and imaginary components:
var arr1 = new Complex128Array( [ 1.0, -1.0, 2.0, -2.0 ] );
// returns <Complex128Array>

var len = arr1.length;
// returns 2

// From an array containing complex numbers:
var buf = [ new Complex128( 1.0, -1.0 ), new Complex128( 2.0, -2.0 ) ];
var arr2 = new Complex128Array( buf );

len = arr2.length;
// returns 2

Complex128Array( buffer[, byteOffset[, length]] )

Returns a 128-bit complex number array view of an ArrayBuffer.

var ArrayBuffer = require( '@stdlib/array-buffer' );
var buf = new ArrayBuffer( 480 );

var arr1 = new Complex128Array( buf );
// returns <Complex128Array>

var len = arr1.length;
// returns 30

var arr2 = new Complex128Array( buf, 16 );
// returns <Complex128Array>

len = arr2.length;
// returns 29

var arr3 = new Complex128Array( buf, 16, 20 );
// returns <Complex128Array>

len = arr3.length;
// returns 20

---

Properties

Complex128Array.BYTES_PER_ELEMENT

Static property returning the size (in bytes) of each array element.

var nbytes = Complex128Array.BYTES_PER_ELEMENT;
// returns 16

Complex128Array.name

Static property returning the constructor name.

var str = Complex128Array.name;
// returns 'Complex128Array'

Complex128Array.prototype.buffer

Pointer to the underlying data buffer.

var arr = new Complex128Array( 2 );
// returns <Complex128Array>

var buf = arr.buffer;
// returns <ArrayBuffer>

Complex128Array.prototype.byteLength

Size (in bytes) of the array.

var arr = new Complex128Array( 10 );
// returns <Complex128Array>

var nbytes = arr.byteLength;
// returns 160

Complex128Array.prototype.byteOffset

Offset (in bytes) of the array from the start of its underlying ArrayBuffer.

var ArrayBuffer = require( '@stdlib/array-buffer' );

var arr = new Complex128Array( 10 );
// returns <Complex128Array>

var offset = arr.byteOffset;
// returns 0

var buf = new ArrayBuffer( 480 );
arr = new Complex128Array( buf, 128 );
// returns <Complex128Array>

offset = arr.byteOffset;
// returns 128

Complex128Array.prototype.BYTES_PER_ELEMENT

Size (in bytes) of each array element.

var arr = new Complex128Array( 10 );
// returns <Complex128Array>

var nbytes = arr.BYTES_PER_ELEMENT;
// returns 16

Complex128Array.prototype.length

Number of array elements.

var arr = new Complex128Array( 10 );
// returns <Complex128Array>

var len = arr.length;
// returns 10

---

Methods

Complex128Array.from( src[, clbk[, thisArg]] )

Creates a new 128-bit complex number array from an array-like object or an iterable.

var Complex128 = require( '@stdlib/complex-float64' );

// Create an array from interleaved real and imaginary components:
var arr = Complex128Array.from( [ 1.0, -1.0 ] );
// returns <Complex128Array>

var len = arr.length;
// returns 1

// Create an array from an array of complex numbers:
arr = Complex128Array.from( [ new Complex128( 1.0, -1.0 ) ] );
// returns <Complex128Array>

len = arr.length;
// returns 1

The iterator returned by an iterable must return either a complex number or an array-like object containing a real and imaginary component.

var ITERATOR_SYMBOL = require( '@stdlib/symbol-iterator' );
var Float64Array = require( '@stdlib/array-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var iter;
var arr;
var len;
var re;
var im;
var z;

// Define a function which returns an iterator protocol-compliant object...
function iterable() {
    var buf = new Float64Array( 2 );
    var i = 0;
    return {
        'next': next
    };

    function next() {
        i += 1;
        if ( i < 3 ) {
            // Reuse allocated memory...
            buf[ 0 ] = i;
            buf[ 1 ] = -i;
            return {
                'value': buf
            };
        }
        return {
            'done': true
        };
    }
}

if ( ITERATOR_SYMBOL === null ) {
    console.error( 'Environment does not support iterables.' );
} else {
    // Create an iterable:
    iter = {};
    iter[ ITERATOR_SYMBOL ] = iterable;

    // Generate a complex number array:
    arr = Complex128Array.from( iter );
    // returns <Complex128Array>

    len = arr.length;
    // returns 2

    z = arr.get( 0 );
    // returns <Complex128>

    re = real( z );
    // returns 1.0

    im = imag( z );
    // returns -1.0
}

To invoke a function for each src value, provide a callback function. If src is an iterable or an array-like object containing complex numbers, the callback must return either a complex number

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function map( z ) {
    return new Complex128( real(z)*2.0, imag(z)*2.0 );
}

// Create a source array:
var src = [ new Complex128( 1.0, -1.0 ) ];

// Create a new complex number array by scaling the source array:
var arr = Complex128Array.from( src, map );
// returns <Complex128Array>

var len = arr.length;
// returns 1

var z = arr.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 2.0

var im = imag( z );
// returns -2.0

or an array-like object containing real and imaginary components

var Float64Array = require( '@stdlib/array-float64' );
var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

// Return a callback which reuses allocated memory...
function mapFcn() {
    var buf = new Float64Array( 2 );
    return map;

    function map( z ) {
        buf[ 0 ] = real( z ) * 2.0;
        buf[ 1 ] = imag( z ) * 2.0;
        return buf;
    }
}

// Create a source array:
var src = [ new Complex128( 1.0, -1.0 ), new Complex128( 2.0, -2.0 ) ];

// Create a new complex number array by scaling the source array:
var arr = Complex128Array.from( src, mapFcn() );
// returns <Complex128Array>

var len = arr.length;
// returns 2

var z = arr.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 2.0

var im = imag( z );
// returns -2.0

z = arr.get( 1 );
// returns <Complex128>

re = real( z );
// returns 4.0

im = imag( z );
// returns -4.0

If src is an array-like object containing interleaved real and imaginary components, the callback is invoked for each component and should return the transformed component value.

var Float64Array = require( '@stdlib/array-float64' );
var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function map( v ) {
    return v * 2.0;
}

// Create a source array:
var src = new Float64Array( [ 1.0, -1.0 ] );

// Create a new complex number array by scaling the source array:
var arr = Complex128Array.from( src, map );
// returns <Complex128Array>

var len = arr.length;
// returns 1

var z = arr.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 2.0

var im = imag( z );
// returns -2.0

A callback function is provided two arguments:

• value: source value.
• index: source index.

To set the callback execution context, provide a thisArg.

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function map( z ) {
    this.count += 1;
    return new Complex128( real(z)*2.0, imag(z)*2.0 );
}

// Create a source array:
var src = [ new Complex128( 1.0, -1.0 ), new Complex128( 1.0, -1.0 ) ];

// Define an execution context:
var ctx = {
    'count': 0
};

// Create a new complex number array by scaling the source array:
var arr = Complex128Array.from( src, map, ctx );
// returns <Complex128Array>

var len = arr.length;
// returns 2

var n = ctx.count;
// returns 2

Complex128Array.of( element0[, element1[, ...elementN]] )

Creates a new 128-bit complex number array from a variable number of arguments.

var Complex128 = require( '@stdlib/complex-float64' );

var arr = Complex128Array.of( 1.0, -1.0, 2.0, -2.0 );
// returns <Complex128Array>

var len = arr.length;
// returns 2

var z1 = new Complex128( 1.0, -1.0 );
var z2 = new Complex128( 2.0, -2.0 );

arr = Complex128Array.of( z1, z2 );
// returns <Complex128Array>

len = arr.length;
// returns 2

Complex128Array.prototype.at( i )

Returns an array element located at integer position (index) i, with support for both nonnegative and negative integer positions.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 10 );

// Set the first, second, and last elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 9.0, -9.0 ], 9 );

// Get the first element:
var z = arr.at( 0 );
// returns <Complex128>

var re = real( z );
// returns 1.0

var im = imag( z );
// returns -1.0

// Get the last element:
z = arr.at( -1 );
// returns <Complex128>

re = real( z );
// returns 9.0

im = imag( z );
// returns -9.0

If provided an out-of-bounds index, the method returns undefined.

var arr = new Complex128Array( 10 );

var z = arr.at( 100 );
// returns undefined

z = arr.at( -100 );
// returns undefined

Complex128Array.prototype.copyWithin( target, start[, end] )

Copies a sequence of elements within the array starting at start and ending at end (non-inclusive) to the position starting at target.

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 4 );

// Set the array elements:
arr.set( new Complex128( 1.0, -1.0 ), 0 );
arr.set( new Complex128( 2.0, -2.0 ), 1 );
arr.set( new Complex128( 3.0, -3.0 ), 2 );
arr.set( new Complex128( 4.0, -4.0 ), 3 );

// Get the first array element:
var z = arr.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 1.0

var im = imag( z );
// returns -1.0

// Get the second array element:
z = arr.get( 1 );
// returns <Complex128>

re = real( z );
// returns 2.0

im = imag( z );
// returns -2.0

// Copy the last two elements to the first two elements:
arr.copyWithin( 0, 2 );

// Get the first array element:
z = arr.get( 0 );
// returns <Complex128>

re = real( z );
// returns 3.0

im = imag( z );
// returns -3.0

// Get the second array element:
z = arr.get( 1 );
// returns <Complex128>

re = real( z );
// returns 4.0

im = imag( z );
// returns -4.0

By default, end equals the number of array elements (i.e., one more than the last array index). To limit the sequence length, provide an end argument.

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 4 );

// Set the array elements:
arr.set( new Complex128( 1.0, -1.0 ), 0 );
arr.set( new Complex128( 2.0, -2.0 ), 1 );
arr.set( new Complex128( 3.0, -3.0 ), 2 );
arr.set( new Complex128( 4.0, -4.0 ), 3 );

// Get the third array element:
var z = arr.get( 2 );
// returns <Complex128>

var re = real( z );
// returns 3.0

var im = imag( z );
// returns -3.0

// Get the last array element:
z = arr.get( 3 );
// returns <Complex128>

re = real( z );
// returns 4.0

im = imag( z );
// returns -4.0

// Copy the first two elements to the last two elements:
arr.copyWithin( 2, 0, 2 );

// Get the third array element:
z = arr.get( 2 );
// returns <Complex128>

re = real( z );
// returns 1.0

im = imag( z );
// returns -1.0

// Get the last array element:
z = arr.get( 3 );
// returns <Complex128>

re = real( z );
// returns 2.0

im = imag( z );
// returns -2.0

When a target, start, and/or end index is negative, the respective index is determined relative to the last array element. The following example achieves the same behavior as the previous example:

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 4 );

// Set the array elements:
arr.set( new Complex128( 1.0, -1.0 ), 0 );
arr.set( new Complex128( 2.0, -2.0 ), 1 );
arr.set( new Complex128( 3.0, -3.0 ), 2 );
arr.set( new Complex128( 4.0, -4.0 ), 3 );

// Get the third array element:
var z = arr.get( 2 );
// returns <Complex128>

var re = real( z );
// returns 3.0

var im = imag( z );
// returns -3.0

// Get the last array element:
z = arr.get( 3 );
// returns <Complex128>

re = real( z );
// returns 4.0

im = imag( z );
// returns -4.0

// Copy the first two elements to the last two elements using negative indices:
arr.copyWithin( -2, -4, -2 );

// Get the third array element:
z = arr.get( 2 );
// returns <Complex128>

re = real( z );
// returns 1.0

im = imag( z );
// returns -1.0

// Get the last array element:
z = arr.get( 3 );
// returns <Complex128>

re = real( z );
// returns 2.0

im = imag( z );
// returns -2.0

Complex128Array.prototype.entries()

Returns an iterator for iterating over array key-value pairs.

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = [
    new Complex128( 1.0, -1.0 ),
    new Complex128( 2.0, -2.0 ),
    new Complex128( 3.0, -3.0 )
];
arr = new Complex128Array( arr );

// Create an iterator:
var it = arr.entries();

// Iterate over the key-value pairs...
var v = it.next().value;
// returns [ 0, <Complex128> ]

var re = real( v[ 1 ] );
// returns 1.0

var im = imag( v[ 1 ] );
// returns -1.0

v = it.next().value;
// returns [ 1, <Complex128> ]

re = real( v[ 1 ] );
// returns 2.0

im = imag( v[ 1 ] );
// returns -2.0

v = it.next().value;
// returns [ 2, <Complex128> ]

re = real( v[ 1 ] );
// returns 3.0

im = imag( v[ 1 ] );
// returns -3.0

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

Complex128Array.prototype.every( predicate[, thisArg] )

Returns a boolean indicating whether all elements pass a test.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v ) {
    return ( real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

// Set the first three elements:
arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

// Check whether all elements pass a test:
var bool = arr.every( predicate );
// returns true

The predicate function is provided three arguments:

• value: current array element.
• index: current array element index.
• arr: the array on which this method was called.

To set the function execution context, provide a thisArg.

function predicate( v, i ) {
    this.count += 1;
    return ( i >= 0 );
}

var arr = new Complex128Array( 3 );

var context = {
    'count': 0
};

// Set the first three elements:
arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var bool = arr.every( predicate, context );
// returns true

var count = context.count;
// returns 3

Complex128Array.prototype.fill( value[, start[, end]] )

Returns a modified typed array filled with a fill value.

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 3 );

// Set all elements to the same value:
arr.fill( new Complex128( 1.0, 1.0 ) );

var z = arr.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 1.0

var im = imag( z );
// returns 1.0

z = arr.get( 2 );
// returns <Complex128>

re = real( z );
// returns 1.0

im = imag( z );
// returns 1.0

// Fill all elements starting from the second element:
arr.fill( new Complex128( 2.0, 2.0 ), 1 );

z = arr.get( 1 );
// returns <Complex128>

re = real( z );
// returns 2.0

im = imag( z );
// returns 2.0

z = arr.get( 2 );
// returns <Complex128>

re = real( z );
// returns 2.0

im = imag( z );
// returns 2.0

// Fill all elements from first element until the second-to-last element:
arr.fill( new Complex128( 3.0, 3.0 ), 0, 2 );

z = arr.get( 0 );
// returns <Complex128>

re = real( z );
// returns 3.0

im = imag( z );
// returns 3.0

z = arr.get( 1 );
// returns <Complex128>

re = real( z );
// returns 3.0

im = imag( z );
// returns 3.0

When a start and/or end index is negative, the respective index is determined relative to the last array element.

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 3 );

// Set all array elements, except the last element, to the same value:
arr.fill( new Complex128( 1.0, 1.0 ), 0, -1 );

var z = arr.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 1.0

var im = imag( z );
// returns 1.0

z = arr.get( arr.length - 1 );
// returns <Complex128>

re = real( z );
// returns 0.0

im = imag( z );
// returns 0.0

Complex128Array.prototype.filter( predicate[, thisArg] )

Returns a new array containing the elements of an array which pass a test implemented by a predicate function.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v ) {
    return ( real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

// Set the first three elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );

var out = arr.filter( predicate );
// returns <Complex128Array>

var len = out.length;
// returns 1

var z = out.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 2.0

var im = imag( z );
// returns 2.0

The predicate function is provided three arguments:

• value: current array element.
• index: current array element index.
• arr: the array on which this method was called.

To set the function execution context, provide a thisArg.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v, i ) {
    this.count += 1;
    return ( i >= 0 && real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

var context = {
    'count': 0
};

// Set the first three elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var out = arr.filter( predicate, context );
// returns <Complex128Array>

var len = out.length;
// returns 2

var count = context.count;
// returns 3

Complex128Array.prototype.find( predicate[, thisArg] )

Returns the first element in an array for which a predicate function returns a truthy value.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v ) {
    return ( real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

// Set the first three elements:
arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var z = arr.find( predicate );
// returns <Complex128>

var re = real( z );
// returns 1.0

var im = imag( z );
// returns 1.0

The predicate function is provided three arguments:

• value: current array element.
• index: current array element index.
• arr: the array on which this method was called.

To set the function execution context, provide a thisArg.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v, i ) {
    this.count += 1;
    return ( i >= 0 && real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

var context = {
    'count': 0
};

// Set the first three elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var z = arr.find( predicate, context );
// returns <Complex128>

var re = real( z );
// returns 2.0

var im = imag( z );
// returns 2.0

var count = context.count;
// returns 2

Complex128Array.prototype.findIndex( predicate[, thisArg] )

Returns the index of the first element in an array for which a predicate function returns a truthy value.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v ) {
    return ( real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

// Set the first three elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var idx = arr.findIndex( predicate );
// returns 2

The predicate function is provided three arguments:

• value: current array element.
• index: current array element index.
• arr: the array on which this method was called.

To set the function execution context, provide a thisArg.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v, i ) {
    this.count += 1;
    return ( i >= 0 && real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

var context = {
    'count': 0
};

// Set the first three elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );

var idx = arr.findIndex( predicate, context );
// returns -1

var count = context.count;
// returns 3

Complex128Array.prototype.findLast( predicate[, thisArg] )

Returns the last element in an array for which a predicate function returns a truthy value.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v ) {
    return ( real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

// Set the first three elements:
arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var z = arr.findLast( predicate );
// returns <Complex128>

var re = real( z );
// returns 3.0

var im = imag( z );
// returns 3.0

The predicate function is provided three arguments:

• value: current array element.
• index: current array element index.
• arr: the array on which this method was called.

To set the function execution context, provide a thisArg.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v, i ) {
    this.count += 1;
    return ( i >= 0 && real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

var context = {
    'count': 0
};

// Set the first three elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );

var z = arr.findLast( predicate, context );
// returns <Complex128>

var re = real( z );
// returns 2.0

var im = imag( z );
// returns 2.0

var count = context.count;
// returns 2

Complex128Array.prototype.findLastIndex( predicate[, thisArg] )

Returns the index of the last element in an array for which a predicate function returns a truthy value.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v ) {
    return ( real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

// Set the first three elements:
arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );

var idx = arr.findLastIndex( predicate );
// returns 1

The predicate function is provided three arguments:

• value: current array element.
• index: current array element index.
• arr: the array on which this method was called.

To set the function execution context, provide a thisArg.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v, i ) {
    this.count += 1;
    return ( i >= 0 && real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

var context = {
    'count': 0
};

// Set the first three elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );

var idx = arr.findLastIndex( predicate, context );
// returns -1

var count = context.count;
// returns 3

Complex128Array.prototype.forEach( callbackFn[, thisArg] )

Invokes a function once for each array element.

var Complex128 = require( '@stdlib/complex-float64' );

function log( v, i ) {
    console.log( '%s: %s', i, v.toString() );
}

var arr = new Complex128Array( 3 );

// Set the first three elements:
arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

arr.forEach( log );
/* =>
    0: 1 + 1i
    1: 2 + 2i
    2: 3 + 3i
*/

The invoked function is provided three arguments:

• value: current array element.
• index: current array element index.
• arr: the array on which this method was called.

To set the function execution context, provide a thisArg.

var Complex128 = require( '@stdlib/complex-float64' );

function fcn( v, i ) {
    this.count += 1;
    console.log( '%s: %s', i, v.toString() );
}

var arr = new Complex128Array( 3 );

var context = {
    'count': 0
};

// Set the first three elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );

arr.forEach( fcn, context );
/* =>
    0: 1 + 1i
    1: 2 + 2i
    2: 3 + 3i
*/

var count = context.count;
// returns 3

Complex128Array.prototype.get( i )

Returns an array element located at position (index) i.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 10 );

// Set the first element:
arr.set( [ 1.0, -1.0 ], 0 );

// Get the first element:
var z = arr.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 1.0

var im = imag( z );
// returns -1.0

If provided an out-of-bounds index, the method returns undefined.

var arr = new Complex128Array( 10 );

var z = arr.get( 100 );
// returns undefined

Complex128Array.prototype.includes( searchElement[, fromIndex] )

Returns a boolean indicating whether an array includes a provided value.

var Complex128 = require( '@stdlib/complex-float64' );

var arr = new Complex128Array( 5 );

arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );
arr.set( [ 4.0, -4.0 ], 3 );
arr.set( [ 5.0, -5.0 ], 4 );

var bool = arr.includes( new Complex128( 3.0, -3.0 ) );
// returns true

bool = arr.includes( new Complex128( 3.0, -3.0 ), 3 );
// returns false

bool = arr.includes( new Complex128( 4.0, -4.0 ), -3 );
// returns true

Complex128Array.prototype.indexOf( searchElement[, fromIndex] )

Returns the first index at which a given element can be found.

var Complex128 = require( '@stdlib/complex-float64' );

var arr = new Complex128Array( 5 );

arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );
arr.set( [ 4.0, -4.0 ], 3 );
arr.set( [ 2.0, -2.0 ], 4 );

var idx = arr.indexOf( new Complex128( 3.0, -3.0 ) );
// returns 2

idx = arr.indexOf( new Complex128( 2.0, -2.0 ), 2 );
// returns 4

idx = arr.indexOf( new Complex128( 4.0, -4.0 ), -3 );
// returns 3

If searchElement is not present in the array, the method returns -1.

var Complex128 = require( '@stdlib/complex-float64' );

var arr = new Complex128Array( 5 );

arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );

var idx = arr.indexOf( new Complex128( 3.0, -3.0 ) );
// returns -1

idx = arr.indexOf( new Complex128( 1.0, -1.0 ), 1 );
// returns -1

Complex128Array.prototype.join( [separator] )

Returns a new string by concatenating all array elements.

var arr = new Complex128Array( 3 );

arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var str = arr.join();
// returns '1 + 1i,2 - 2i,3 + 3i'

By default, the method separates serialized array elements with a comma. To use an alternative separator, provide a separator string.

var arr = new Complex128Array( 3 );

arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var str = arr.join( '/' );
// returns '1 + 1i/2 - 2i/3 + 3i'

Complex128Array.prototype.lastIndexOf( searchElement[, fromIndex] )

Returns the last index at which a given element can be found.

var Complex128 = require( '@stdlib/complex-float64' );

var arr = new Complex128Array( 5 );

arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );
arr.set( [ 4.0, -4.0 ], 3 );
arr.set( [ 2.0, -2.0 ], 4 );

var idx = arr.lastIndexOf( new Complex128( 3.0, -3.0 ) );
// returns 2

idx = arr.lastIndexOf( new Complex128( 2.0, -2.0 ), 2 );
// returns 1

idx = arr.lastIndexOf( new Complex128( 4.0, -4.0 ), -1 );
// returns 3

If searchElement is not present in the array, the method returns -1.

var Complex128 = require( '@stdlib/complex-float64' );

var arr = new Complex128Array( 5 );

arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );

var idx = arr.lastIndexOf( new Complex128( 3.0, -3.0 ) );
// returns -1

idx = arr.lastIndexOf( new Complex128( 2.0, -2.0 ), 0 );
// returns -1

Complex128Array.prototype.map( callbackFn[, thisArg] )

Returns a new array with each element being the result of a provided callback function.

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function scale( v ) {
    return new Complex128( 2.0*real( v ), 2.0*imag( v ) );
}

var arr = new Complex128Array( 3 );

// Set the first three elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );

var out = arr.map( scale );
// returns <Complex128Array>

var z = out.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 2.0

var im = imag( z );
// returns -2.0

The callback function is provided three arguments:

• value: current array element.
• index: current array element index.
• arr: the array on which this method was called.

To set the function execution context, provide a thisArg.

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function scale( v ) {
    this.count += 1;
    return new Complex128( 2.0*real( v ), 2.0*imag( v ) );
}

var arr = new Complex128Array( 3 );

var context = {
    'count': 0
};

// Set the first three elements:
arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var out = arr.map( scale, context );
// returns <Complex128Array>

var count = context.count;
// returns 3

Complex128Array.prototype.reduce( reducerFn[, initialValue] )

Applies a provided callback function to each element of the array, in order, passing in the return value from the calculation on the preceding element and returning the accumulated result upon completion.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );
var cadd = require( '@stdlib/math-base-ops-cadd' );

var arr = new Complex128Array( 3 );

arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var z = arr.reduce( cadd );
// returns <Complex128>

var re = real( z );
// returns 6.0

var im = imag( z );
// returns 6.0

The reducer function is provided four arguments:

• acc: accumulated result.
• value: current array element.
• index: current array element index.
• arr: the array on which this method was called.

By default, the function initializes the accumulated result to the first element in the array and passes the second array element as value during the first invocation of the provided callback. To begin accumulation from a different starting value and pass in the first array element as value during the first invocation of the provided callback, provide an initialValue argument.

var real = require( '@stdlib/complex-real' );

function reducer( acc, v ) {
    acc += real( v );
    return acc;
}

var arr = new Complex128Array( 3 );

arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var z = arr.reduce( reducer, 0.0 );
// returns 6.0

Complex128Array.prototype.reverse()

Reverses an array in-place.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 3 );

arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var out = arr.reverse();
// returns <Complex128Array>

var z = out.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 3.0

var im = imag( z );
// returns 3.0

z = out.get( 1 );
// returns <Complex128>

re = real( z );
// returns 2.0

im = imag( z );
// returns 2.0

z = out.get( 2 );
// returns <Complex128>

re = real( z );
// returns 1.0

im = imag( z );
// returns 1.0

Complex128Array.prototype.set( z[, i] )

Sets one or more array elements.

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 10 );

// Get the first element:
var z = arr.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 0.0

var im = imag( z );
// returns 0.0

// Set the first element:
arr.set( new Complex128( 1.0, -1.0 ) );

// Get the first element:
z = arr.get( 0 );
// returns <Complex128>

re = real( z );
// returns 1.0

im = imag( z );
// returns -1.0

By default, the method sets array elements starting at position (index) i = 0. To set elements starting elsewhere in the array, provide an index argument i.

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 10 );

// Get the fifth element:
var z = arr.get( 4 );
// returns <Complex128>

var re = real( z );
// returns 0.0

var im = imag( z );
// returns 0.0

// Set the fifth element:
arr.set( new Complex128( 1.0, -1.0 ), 4 );

// Get the fifth element:
z = arr.get( 4 );
// returns <Complex128>

re = real( z );
// returns 1.0

im = imag( z );
// returns -1.0

In addition to providing a complex number, to set one or more array elements, provide an array-like object containing either complex numbers

var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 10 );

// Define an array of complex numbers:
var buf = [
    new Complex128( 1.0, -1.0 ),
    new Complex128( 2.0, -2.0 ),
    new Complex128( 3.0, -3.0 )
];

// Set the fifth, sixth, and seventh elements:
arr.set( buf, 4 );

// Get the sixth element:
var z = arr.get( 5 );
// returns <Complex128>

var re = real( z );
// returns 2.0

var im = imag( z );
// returns -2.0

or interleaved real and imaginary components

var Float64Array = require( '@stdlib/array-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 10 );

// Define an interleaved array of real and imaginary components:
var buf = new Float64Array( [ 1.0, -1.0, 2.0, -2.0, 3.0, -3.0 ] );

// Set the fifth, sixth, and seventh elements:
arr.set( buf, 4 );

// Get the sixth element:
var z = arr.get( 5 );
// returns <Complex128>

var re = real( z );
// returns 2.0

var im = imag( z );
// returns -2.0

A few notes:

• If i is out-of-bounds, the method throws an error.
• If a target array cannot accommodate all values (i.e., the length of source array plus i exceeds the target array length), the method throws an error.
• If provided a typed array which shares an ArrayBuffer with the target array, the method will intelligently copy the source range to the destination range.

Complex128Array.prototype.slice( [start[, end]] )

Copies a portion of a typed array to a new typed array.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] );

var out = arr.slice();
// returns <Complex128Array>

var len = out.length;
// returns 4

var z = out.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 1.0

var im = imag( z );
// returns 2.0

z = out.get( len-1 );
// returns <Complex128>

re = real( z );
// returns 7.0

im = imag( z );
// returns 8.0

By default, the method returns a typed array beginning with the first array element. To specify an alternative array index at which to begin, provide a start index (inclusive).

var imag = require( '@stdlib/complex-imag' );
var real = require( '@stdlib/complex-real' );

var arr = new Complex128Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] );

var out = arr.slice( 1 );
// returns <Complex128Array>

var len = out.length;
// returns 3

var z = out.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 3.0

var im = imag( z );
// returns 4.0

By default, the method returns a typed array which includes all array elements after start. To limit the number of array elements after start, provide an end index (exclusive).

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] );

var out = arr.slice( 1, -1 );
// returns <Complex128Array>

var len = out.length;
// returns 2

var z = out.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 3.0

var im = imag( z );
// returns 4.0

z = out.get( len-1 );
// returns <Complex128>

re = real( z );
// returns 5.0

im = imag( z );
// returns 6.0

Complex128Array.prototype.some( predicate[, thisArg] )

Returns a boolean indicating whether at least one element passes a test.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v ) {
    return ( real( v ) === imag( v ) );
}

var arr = new Complex128Array( 3 );

// Set the first three elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );

// Check whether at least one element passes a test:
var bool = arr.some( predicate );
// returns true

The predicate function is provided three arguments:

• value: current array element.
• index: current array element index.
• arr: the array on which this method was called.

To set the function execution context, provide a thisArg.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

function predicate( v, i ) {
    this.count += 1;
    return ( imag( v ) === real( v ) );
}

var arr = new Complex128Array( 3 );

var context = {
    'count': 0
};

// Set the first three elements:
arr.set( [ 1.0, -1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, -3.0 ], 2 );

var bool = arr.some( predicate, context );
// returns true

var count = context.count;
// returns 2

Complex128Array.prototype.subarray( [begin[, end]] )

Creates a new typed array view over the same underlying ArrayBuffer and with the same underlying data type as the host array.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] );

var subarr = arr.subarray();
// returns <Complex128Array>

var len = subarr.length;
// returns 4

var z = subarr.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 1.0

var im = imag( z );
// returns 2.0

z = subarr.get( len-1 );
// returns <Complex128>

re = real( z );
// returns 7.0

im = imag( z );
// returns 8.0

By default, the method creates a typed array view beginning with the first array element. To specify an alternative array index at which to begin, provide a begin index (inclusive).

var imag = require( '@stdlib/complex-imag' );
var real = require( '@stdlib/complex-real' );

var arr = new Complex128Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] );

var subarr = arr.subarray( 1 );
// returns <Complex128Array>

var len = subarr.length;
// returns 3

var z = subarr.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 3.0

var im = imag( z );
// returns 4.0

By default, the method creates a typed array view which includes all array elements after begin. To limit the number of array elements after begin, provide an end index (exclusive).

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] );

var subarr = arr.subarray( 1, -1 );
// returns <Complex128Array>

var len = subarr.length;
// returns 2

var z = subarr.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 3.0

var im = imag( z );
// returns 4.0

z = subarr.get( len-1 );
// returns <Complex128>

re = real( z );
// returns 5.0

im = imag( z );
// returns 6.0

Complex128Array.prototype.toReversed()

Returns a new typed array containing the elements in reversed order.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );

var arr = new Complex128Array( 3 );

arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var out = arr.toReversed();
// returns <Complex128Array>

var z = out.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 3.0

var im = imag( z );
// returns 3.0

z = out.get( 1 );
// returns <Complex128>

re = real( z );
// returns 2.0

im = imag( z );
// returns 2.0

z = out.get( 2 );
// returns <Complex128>

re = real( z );
// returns 1.0

im = imag( z );
// returns 1.0

Complex128Array.prototype.toString()

Serializes an array as a string.

var arr = new Complex128Array( 3 );

arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, -2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 2 );

var str = arr.toString();
// returns '1 + 1i,2 - 2i,3 + 3i'

Complex128Array.prototype.with( index, value )

Returns a new typed array with the element at a provided index replaced with a provided value.

var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-imag' );
var Complex128 = require( '@stdlib/complex-float64' );

var arr = new Complex128Array( 3 );

arr.set( [ 1.0, 1.0 ], 0 );
arr.set( [ 2.0, 2.0 ], 1 );
arr.set( [ 3.0, 3.0 ], 1 );

var out = arr.with( 0, new Complex128( 4.0, 4.0 ) );
// returns <Complex128Array>

var z = out.get( 0 );
// returns <Complex128>

var re = real( z );
// returns 4.0

var im = imag( z );
// returns 4.0

---

Notes

• While a Complex128Array strives to maintain (but does not guarantee) consistency with typed arrays, significant deviations from ECMAScript-defined typed array behavior are as follows:

  • The constructor does not require the new operator.
  • The constructor and associated methods support a broader variety of input argument types in order to better accommodate complex number input.
  • Accessing array elements using bracket syntax (e.g., Z[i]) is not supported. Instead, one must use the .get() method which returns a value compatible with complex number output.
  • The set method has extended behavior in order to support complex numbers.

---

Examples

var Complex128 = require( '@stdlib/complex-float64' );
var Float64Array = require( '@stdlib/array-float64' );
var logEach = require( '@stdlib/console-log-each' );
var Complex128Array = require( '@stdlib/array-complex128' );

// Create a complex array by specifying a length:
var out = new Complex128Array( 3 );
logEach( '%s', out );

// Create a complex array from an array of complex numbers:
var arr = [
    new Complex128( 1.0, -1.0 ),
    new Complex128( -3.14, 3.14 ),
    new Complex128( 0.5, 0.5 )
];
out = new Complex128Array( arr );
logEach( '%s', out );

// Create a complex array from an interleaved typed array:
arr = new Float64Array( [ 1.0, -1.0, -3.14, 3.14, 0.5, 0.5 ] );
out = new Complex128Array( arr );
logEach( '%s', out );

// Create a complex array from an array buffer:
arr = new Float64Array( [ 1.0, -1.0, -3.14, 3.14, 0.5, 0.5 ] );
out = new Complex128Array( arr.buffer );
logEach( '%s', out );

// Create a complex array from an array buffer view:
arr = new Float64Array( [ 1.0, -1.0, -3.14, 3.14, 0.5, 0.5 ] );
out = new Complex128Array( arr.buffer, 16, 2 );
logEach( '%s', out );

---

See Also

• @stdlib/array-complex64: Complex64Array.
• @stdlib/complex-cmplx: create a complex number.
• @stdlib/complex-float64: 128-bit complex number.

---

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.