Float64Array
============

Объект **`Float64Array`** представляет типизированный массив 64-битных чисел с плавающей запятой (соответствует типу `double` в языке C) с платформо-зависимым порядком байт.Если необходим контроль за порядком байт, то вместо этого объекта используйте `DataView`. Содержимое инициализируется значением `0`. Создав экземпляр **`Float64Array`** , можно получить доступ к элементам массива, используя методы объекта или стандартный синтаксис доступа к элементу массива по его индексу (с помощью скобочной нотации - квадратные скобки).

Syntax
------
```

new Float64Array(); // new in ES2017
new Float64Array(length);
new Float64Array(typedArray);
new Float64Array(object);
new Float64Array(buffer [, byteOffset [, length]]);
```


For more information about the constructor syntax and the parameters, see *TypedArray*.

Properties
----------

`Float64Array.BYTES_PER_ELEMENT`

Returns a number value of the element size. `8` in the case of an `Float64Array`.

Float64Array.length

Static length property whose value is 0. For the actual length (number of elements), see `Float64Array.prototype.length` (en-US).

`Float64Array.name` (en-US)

Returns the string value of the constructor name. In the case of the `Float64Array` type: "Float64Array".

`Float64Array.prototype` (en-US)

Prototype for the *TypedArray* objects.

Methods
-------

`Float64Array.from()` (en-US)

Creates a new `Float64Array` from an array-like or iterable object. See also `Array.from()`.

`Float64Array.of()` (en-US)

Creates a new `Float64Array` with a variable number of arguments. See also `Array.of()`.

`Float64Array` prototype
------------------------

All `Float64Array` objects inherit from `%TypedArray%.prototype` (en-US).

### Properties

`Float64Array.prototype.constructor`

Returns the function that created an instance's prototype. This is the `Float64Array` constructor by default.

`Float64Array.prototype.buffer` (en-US) Только для чтения 

Returns the `ArrayBuffer` referenced by the `Float64Array` Fixed at construction time and thus **read only**.

`Float64Array.prototype.byteLength` (en-US) Только для чтения 

Returns the length (in bytes) of the `Float64Array` from the start of its `ArrayBuffer`. Fixed at construction time and thus **read only.**

`Float64Array.prototype.byteOffset` (en-US) Только для чтения 

Returns the offset (in bytes) of the `Float64Array` from the start of its `ArrayBuffer`. Fixed at construction time and thus **read only.**

`Float64Array.prototype.length` (en-US) Только для чтения 

Returns the number of elements hold in the `Float64Array`. Fixed at construction time and thus **read only.**

### Methods

`Float64Array.prototype.copyWithin()` (en-US)

Copies a sequence of array elements within the array. See also `Array.prototype.copyWithin()`.

`Float64Array.prototype.entries()` (en-US)

Returns a new `Array Iterator` object that contains the key/value pairs for each index in the array. See also `Array.prototype.entries()`.

`Float64Array.prototype.every()` (en-US)

Tests whether all elements in the array pass the test provided by a function. See also `Array.prototype.every()`.

`Float64Array.prototype.fill()` (en-US)

Fills all the elements of an array from a start index to an end index with a static value. See also `Array.prototype.fill()`.

`Float64Array.prototype.filter()` (en-US)

Creates a new array with all of the elements of this array for which the provided filtering function returns true. See also `Array.prototype.filter()`.

`Float64Array.prototype.find()` (en-US)

Returns the found value in the array, if an element in the array satisfies the provided testing function or `undefined` if not found. See also `Array.prototype.find()`.

`Float64Array.prototype.findIndex()` (en-US)

Returns the found index in the array, if an element in the array satisfies the provided testing function or -1 if not found. See also `Array.prototype.findIndex()`.

`Float64Array.prototype.forEach()` (en-US)

Calls a function for each element in the array. See also `Array.prototype.forEach()`.

`Float64Array.prototype.includes()` (en-US) 
Экспериментальная возможность

Determines whether a typed array includes a certain element, returning `true` or `false` as appropriate. See also `Array.prototype.includes()`.

`Float64Array.prototype.indexOf()` (en-US)

Returns the first (least) index of an element within the array equal to the specified value, or -1 if none is found. See also `Array.prototype.indexOf()`.

`Float64Array.prototype.join()`

Joins all elements of an array into a string. See also `Array.prototype.join()`.

`Float64Array.prototype.keys()` (en-US)

Returns a new `Array Iterator` that contains the keys for each index in the array. See also `Array.prototype.keys()`.

`Float64Array.prototype.lastIndexOf()` (en-US)

Returns the last (greatest) index of an element within the array equal to the specified value, or -1 if none is found. See also `Array.prototype.lastIndexOf()`.

`Float64Array.prototype.map()` (en-US)

Creates a new array with the results of calling a provided function on every element in this array. See also `Array.prototype.map()`.

`Float64Array.prototype.move()` 
Non-standard
 Не реализовано

Former non-standard version of `Float64Array.prototype.copyWithin()` (en-US).

`Float64Array.prototype.reduce()` (en-US)

Apply a function against an accumulator and each value of the array (from left-to-right) as to reduce it to a single value. See also `Array.prototype.reduce()`.

`Float64Array.prototype.reduceRight()` (en-US)

Apply a function against an accumulator and each value of the array (from right-to-left) as to reduce it to a single value. See also `Array.prototype.reduceRight()`.

`Float64Array.prototype.reverse()` (en-US)

Reverses the order of the elements of an array — the first becomes the last, and the last becomes the first. See also `Array.prototype.reverse()`.

`Float64Array.prototype.set()`

Stores multiple values in the typed array, reading input values from a specified array.

`Float64Array.prototype.slice()` (en-US)

Extracts a section of an array and returns a new array. See also `Array.prototype.slice()`.

`Float64Array.prototype.some()` (en-US)

Returns true if at least one element in this array satisfies the provided testing function. See also `Array.prototype.some()`.

`Float64Array.prototype.sort()` (en-US)

Sorts the elements of an array in place and returns the array. See also `Array.prototype.sort()`.

`Float64Array.prototype.subarray()` (en-US)

Returns a new `Float64Array` from the given start and end element index.

`Float64Array.prototype.values()` (en-US)

Returns a new `Array Iterator` object that contains the values for each index in the array. See also `Array.prototype.values()`.

`Float64Array.prototype.toLocaleString()` (en-US)

Returns a localized string representing the array and its elements. See also `Array.prototype.toLocaleString()`.

`Float64Array.prototype.toString()` (en-US)

Returns a string representing the array and its elements. See also `Array.prototype.toString()`.

`Float64Array.prototype[@@iterator]()` (en-US)

Returns a new `Array Iterator` object that contains the values for each index in the array.

Examples
--------

Different ways to create a `Float64Array`:


```js
// From a length
var float64 = new Float64Array(2);
float64[0] = 42;
console.log(float64[0]); // 42
console.log(float64.length); // 2
console.log(float64.BYTES\_PER\_ELEMENT); // 8

// From an array
var arr = new Float64Array([21, 31]);
console.log(arr[1]); // 31

// From another TypedArray
var x = new Float64Array([21, 31]);
var y = new Float64Array(x);
console.log(y[0]); // 21

// From an ArrayBuffer
var buffer = new ArrayBuffer(32);
var z = new Float64Array(buffer, 0, 4);

// From an iterable
var iterable = (function\* () {
  yield\* [1, 2, 3];
})();
var float64 = new Float64Array(iterable);
// Float64Array[1, 2, 3]
```

Specifications
--------------

| Specification |
| --- |
| ECMAScript Language Specification # table-49 |

Совместимость с браузерами
--------------------------

BCD tables only load in the browser with JavaScript enabled. Enable JavaScript to view data.

Compatibility notes
-------------------

Starting with ECMAScript 2015, `Float64Array` constructors require to be constructed with a `new` operator. Calling a `Float64Array` constructor as a function without `new`, will throw a `TypeError` from now on.


```js
var dv = Float64Array([1, 2, 3]);
// TypeError: calling a builtin Float64Array constructor
// without new is forbidden
```



```js
var dv = new Float64Array([1, 2, 3]);
```

See also
--------

* JavaScript typed arrays
* `ArrayBuffer`
* `DataView`