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add

Add two 64-bit unsigned integers.

Installation

npm install @stdlib/number-uint64-base-add

Alternatively,

• To load the package in a website via a script tag without installation and bundlers, use the ES Module available on the esm branch (see README).
• If you are using Deno, visit the deno branch (see README for usage intructions).
• For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the umd branch (see README).

The branches.md file summarizes the available branches and displays a diagram illustrating their relationships.

To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.

Usage

var add = require( '@stdlib/number-uint64-base-add' );

add( a, b )

Adds two 64-bit unsigned integers.

var Uint64 = require( '@stdlib/number-uint64-ctor' );

var a = new Uint64( 5 );
var b = new Uint64( 10 );

var v = add( a, b );
// returns <Uint64>[ 15n ]

add.assign( ah, al, bh, bl, out, so, oo )

Adds two 64-bit unsigned integers and assigns results to a provided output array.

var Uint32Array = require( '@stdlib/array-uint32' );

var out = new Uint32Array( 2 );
var v = add.assign( 0, 5, 0, 10, out, 1, 0 );
// returns <Uint32Array>[ 0, 15 ]

var bool = ( out === v );
// returns true

The function supports the following parameters:

• ah: high 32-bit word of the first 64-bit unsigned integer.
• al: low 32-bit word of the first 64-bit unsigned integer.
• bh: high 32-bit word of the second 64-bit unsigned integer.
• bl: low 32-bit word of the second 64-bit unsigned integer.
• out: output array.
• so: stride length for out.
• oo: starting index for out.

add.strided( a, sa, oa, b, sb, ob, out, so, oo )

Adds two 64-bit unsigned integers stored in integer-valued strided array views and assigns results to a provided strided output array.

var Uint32Array = require( '@stdlib/array-uint32' );

var a = new Uint32Array( [ 0, 5 ] );
var b = new Uint32Array( [ 0, 10 ] );
var out = new Uint32Array( 2 );

var v = add.strided( a, 1, 0, b, 1, 0, out, 1, 0 );
// returns <Uint32Array>[ 0, 15 ]

var bool = ( out === v );
// returns true

The function supports the following parameters:

• a: first 64-bit unsigned integer strided array view containing interleaved 32-bit unsigned integer high and low order words.
• sa: stride length for a.
• oa: starting index for a.
• b: second 64-bit unsigned integer strided array view containing interleaved 32-bit unsigned integer high and low order words.
• sb: stride length for b.
• ob: starting index for b.
• out: output array.
• so: stride length for out.
• oo: starting index for out.

Examples

var Uint64 = require( '@stdlib/number-uint64-ctor' );
var add = require( '@stdlib/number-uint64-base-add' );

var a = new Uint64( 5 );
var b = new Uint64( 10 );
var v = add( a, b );
// returns <Uint64>[ 15n ]

a = new Uint64( 1234567890 );
b = new Uint64( 8765432109 );
v = add( a, b );
// returns <Uint64>[ 9999999999n ]

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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

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License

See LICENSE.

Copyright

Copyright © 2016-2026. The Stdlib Authors.