Skip to content

Latest commit

 

History

History
428 lines (281 loc) · 14.2 KB

README.md

File metadata and controls

428 lines (281 loc) · 14.2 KB
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!

SharedArrayBuffer

NPM version Build Status Coverage Status

Constructor returning an object used to represent a generic, fixed-length raw binary data buffer which can be used to create views of shared memory.

Usage

To use in Observable,

SharedArrayBuffer = require( 'https://cdn.jsdelivr.net/gh/stdlib-js/array-shared-buffer@umd/browser.js' )

To vendor stdlib functionality and avoid installing dependency trees for Node.js, you can use the UMD server build:

var SharedArrayBuffer = require( 'path/to/vendor/umd/array-shared-buffer/index.js' )

To include the bundle in a webpage,

<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/stdlib-js/array-shared-buffer@umd/browser.js"></script>

If no recognized module system is present, access bundle contents via the global scope:

<script type="text/javascript">
(function () {
    window.SharedArrayBuffer;
})();
</script>

SharedArrayBuffer( size )

Returns a SharedArrayBuffer having a specified number of bytes.

try {
    var buf = new SharedArrayBuffer( 5 );
    // returns <SharedArrayBuffer>
} catch ( err ) {
    console.log( 'Environment does not support SharedArrayBuffers.' );
}

Properties

SharedArrayBuffer.length

Number of input arguments the constructor accepts.

var len = SharedArrayBuffer.length;
// returns 1

SharedArrayBuffer.prototype.byteLength

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

try {
    var buf = new SharedArrayBuffer( 5 );
    var byteLength = buf.byteLength;
    // returns 5
} catch ( err ) {
    console.log( 'Environment does not support SharedArrayBuffers.' );
}

Methods

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

Copies the bytes of a SharedArrayBuffer to a new SharedArrayBuffer.

try {
    var b1 = new SharedArrayBuffer( 10 );

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

    var bool = ( b2 === b1 );
    // returns false
} catch ( err ) {
    console.log( 'Environment does not support SharedArrayBuffers.' );
}

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

try {
    var b1 = new SharedArrayBuffer( 10 );
    var b2 = b1.slice( 2 );

    var nbytes = b2.byteLength;
    // returns 8
} catch ( err ) {
    console.log( 'Environment does not support SharedArrayBuffers.' );
}

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

try {
    var b1 = new SharedArrayBuffer( 10 );
    var b2 = b1.slice( -2 );

    var nbytes = b2.byteLength;
    // returns 2
} catch ( err ) {
    console.log( 'Environment does not support SharedArrayBuffers.' );
}

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

try {
    var b1 = new SharedArrayBuffer( 10 );
    var b2 = b1.slice( 2, 6 );

    var nbytes = b2.byteLength;
    // returns 4
} catch ( err ) {
    console.log( 'Environment does not support SharedArrayBuffers.' );
}

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

try {
    var b1 = new SharedArrayBuffer( 10 );
    var b2 = b1.slice( 2, -2 );

    var nbytes = b2.byteLength;
    // returns 6
} catch ( err ) {
    console.log( 'Environment does not support SharedArrayBuffers.' );
}

Examples

<!DOCTYPE html>
<html lang="en">
<body>
<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/stdlib-js/random-base-randu@umd/browser.js"></script>
<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/stdlib-js/array-float64@umd/browser.js"></script>
<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/stdlib-js/array-uint8@umd/browser.js"></script>
<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/stdlib-js/number-uint8-base-to-binary-string@umd/browser.js"></script>
<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/stdlib-js/array-shared-buffer@umd/browser.js"></script>
<script type="text/javascript">
(function () {

function main() {
    var bytes;
    var buf;
    var arr;
    var i;

    // Create a new SharedArrayBuffer:
    buf = new SharedArrayBuffer( 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 ] ) );
    }
}

try {
    main();
} catch ( err ) {
    console.error( 'Environment does not provide SharedArrayBuffer support.' );
}

})();
</script>
</body>
</html>

See Also


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

Chat


License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.