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About stdlib...

We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.

The library is fully decomposable, being architected in such a way that you can swap out and mix and match APIs and functionality to cater to your exact preferences and use cases.

When you use stdlib, you can be absolutely certain that you are using the most thorough, rigorous, well-written, studied, documented, tested, measured, and high-quality code out there.

To join us in bringing numerical computing to the web, get started by checking us out on GitHub, and please consider financially supporting stdlib. We greatly appreciate your continued support!

ArrayBuffer

NPM version Build Status Coverage Status

Constructor which returns an object used to represent a generic, fixed-length raw binary data buffer.

Usage

import ArrayBuffer from 'https://cdn.jsdelivr.net/gh/stdlib-js/array-buffer@esm/index.mjs';

ArrayBuffer( size )

Returns an ArrayBuffer having a specified number of bytes.

var buf = new ArrayBuffer( 5 );
// returns <ArrayBuffer>

Properties

ArrayBuffer.length

Number of input arguments the constructor accepts.

var len = ArrayBuffer.length;
// returns 1

ArrayBuffer.prototype.byteLength

Read-only property which returns the length (in bytes) of the ArrayBuffer.

var buf = new ArrayBuffer( 5 );
var byteLength = buf.byteLength;
// returns 5

Methods

ArrayBuffer.isView( arr )

Static method which returns a boolean indicating if provided a buffer view.

import Float64Array from 'https://cdn.jsdelivr.net/gh/stdlib-js/array-float64@esm/index.mjs';
var view = new Float64Array( 10 );

var bool = ArrayBuffer.isView( view );
// returns true

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

Copies the bytes of an ArrayBuffer to a new ArrayBuffer.

var b1 = new ArrayBuffer( 10 );

var b2 = b1.slice();
// returns <ArrayBuffer>

var bool = ( b2 === b1 );
// returns false

By default, the method copies from the beginning of the ArrayBuffer. To beginning copying from a different byte index, provide a start argument, specifying the starting byte index (inclusive).

var b1 = new ArrayBuffer( 10 );
var b2 = b1.slice( 2 );

var nbytes = b2.byteLength;
// returns 8

If start < 0, the index is relative to the end of the ArrayBuffer.

var b1 = new ArrayBuffer( 10 );
var b2 = b1.slice( -2 );

var nbytes = b2.byteLength;
// returns 2

By default, the method copies to the end of the ArrayBuffer. To copy until a particular byte index, provide an end index, specifying the ending byte index (exclusive).

var b1 = new ArrayBuffer( 10 );
var b2 = b1.slice( 2, 6 );

var nbytes = b2.byteLength;
// returns 4

If end < 0, the index is relative to the end of the ArrayBuffer.

var b1 = new ArrayBuffer( 10 );
var b2 = b1.slice( 2, -2 );

var nbytes = b2.byteLength;
// returns 6

Examples

<!DOCTYPE html>
<html lang="en">
<body>
<script type="module">

import randu from 'https://cdn.jsdelivr.net/gh/stdlib-js/random-base-randu@esm/index.mjs';
import Float64Array from 'https://cdn.jsdelivr.net/gh/stdlib-js/array-float64@esm/index.mjs';
import Uint8Array from 'https://cdn.jsdelivr.net/gh/stdlib-js/array-uint8@esm/index.mjs';
import toBinaryString from 'https://cdn.jsdelivr.net/gh/stdlib-js/number-uint8-base-to-binary-string@esm/index.mjs';
import ArrayBuffer from 'https://cdn.jsdelivr.net/gh/stdlib-js/array-buffer@esm/index.mjs';

var bytes;
var buf;
var arr;
var i;

// Create a new ArrayBuffer:
buf = new ArrayBuffer( 64 );

// Create a Float64 array buffer view:
arr = new Float64Array( buf.byteLength/8 );
for ( i = 0; i < arr.length; i++ ) {
    arr[ i ] = randu() * 100.0;
}

// Create a "bytes" view of the array buffer:
bytes = new Uint8Array( arr.buffer );

// Print the bytes:
for ( i = 0; i < bytes.length; i++ ) {
    console.log( 'byte %d: %s', i, toBinaryString( bytes[ i ] ) );
}

</script>
</body>
</html>

See Also

Notice

This package is part of stdlib, a standard library 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

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License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.