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Perform C-like multiplication of two signed 32-bit integers.

License: Apache License 2.0

JavaScript 35.20% Makefile 45.08% C 19.72%

math-base-special-imul's Introduction

Attention

⚠️ This package has been renamed. Use @stdlib/math-base-ops-imul instead. ⚠️

imul

$Build Status$

Perform C-like multiplication of two signed 32-bit integers.

Installation

npm install @stdlib/math-base-special-imul

Usage

var imul = require( '@stdlib/math-base-special-imul' );

imul( a, b )

Performs C-like multiplication of two signed 32-bit integers.

var v = imul( -10|0, 4|0 );
// returns -40

v = imul( 1073741824|0, -5|0 ); // 2^30 * -5 = -5368709120 => 32-bit integer overflow
// returns -1073741824

Notes

The function emulates C-like multiplication of two signed 32-bit integers.

Examples

var discreteUniform = require( '@stdlib/random-base-discrete-uniform' ).factory;
var INT32_MIN = require( '@stdlib/constants-int32-min' );
var INT32_MAX = require( '@stdlib/constants-int32-max' );
var imul = require( '@stdlib/math-base-special-imul' );

var randi;
var a;
var b;
var y;
var i;

randi = discreteUniform( INT32_MIN, INT32_MAX );

for ( i = 0; i < 100; i++ ) {
    a = randi()|0;
    b = randi()|0;
    y = imul( a, b );
    console.log( '%d x %d = %d', a, b, y );
}

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.