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math-float64-get-low-word

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Returns a 32-bit integer corresponding to the less significant 32 bits of a double-precision floating-point number.

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Low Word === [![NPM version][npm-image]][npm-url] [![Build Status][build-image]][build-url] [![Coverage Status][coverage-image]][coverage-url] [![Dependencies][dependencies-image]][dependencies-url] > Returns an unsigned 32-bit integer corresponding to the less significant 32 bits of a [double-precision floating-point number][ieee754]. ## Installation ``` bash $ npm install math-float64-get-low-word ``` ## Usage ``` javascript var lowWord = require( 'math-float64-get-low-word' ); ``` #### lowWord( x ) Returns an unsigned 32-bit `integer` corresponding to the less significant 32 bits of a [double-precision floating-point number][ieee754]. ``` javascript var w = lowWord( 3.14e201 ); // returns 2479577218 => 10010011110010110101100010000010 ``` ## Examples ``` javascript var floor = require( 'math-floor' ); var pow = require( 'math-power' ); var lowWord = require( 'math-float64-get-low-word' ); var frac; var exp; var w; var x; var i; for ( i = 0; i < 100; i++ ) { frac = Math.random() * 10; exp = -floor( Math.random()*324 ); x = frac * pow( 10, exp ); w = lowWord( x ); console.log( 'x: %d. low word: %d.', x, w ); } ``` To run the example code from the top-level application directory, ``` bash $ node ./examples/index.js ``` --- ## Tests ### Unit This repository uses [tape][tape] for unit tests. To run the tests, execute the following command in the top-level application directory: ``` bash $ make test ``` All new feature development should have corresponding unit tests to validate correct functionality. ### Test Coverage This repository uses [Istanbul][istanbul] as its code coverage tool. To generate a test coverage report, execute the following command in the top-level application directory: ``` bash $ make test-cov ``` Istanbul creates a `./reports/coverage` directory. To access an HTML version of the report, ``` bash $ make view-cov ``` ### Browser Support This repository uses [Testling][testling] for browser testing. To run the tests in a (headless) local web browser, execute the following command in the top-level application directory: ``` bash $ make test-browsers ``` To view the tests in a local web browser, ``` bash $ make view-browser-tests ``` <!-- [![browser support][browsers-image]][browsers-url] --> --- ## License [MIT license](http://opensource.org/licenses/MIT). ## Copyright Copyright &copy; 2016. The [Compute.io][compute-io] Authors. [npm-image]: http://img.shields.io/npm/v/math-float64-get-low-word.svg [npm-url]: https://npmjs.org/package/math-float64-get-low-word [build-image]: http://img.shields.io/travis/math-io/float64-get-low-word/master.svg [build-url]: https://travis-ci.org/math-io/float64-get-low-word [coverage-image]: https://img.shields.io/codecov/c/github/math-io/float64-get-low-word/master.svg [coverage-url]: https://codecov.io/github/math-io/float64-get-low-word?branch=master [dependencies-image]: http://img.shields.io/david/math-io/float64-get-low-word.svg [dependencies-url]: https://david-dm.org/math-io/float64-get-low-word [dev-dependencies-image]: http://img.shields.io/david/dev/math-io/float64-get-low-word.svg [dev-dependencies-url]: https://david-dm.org/dev/math-io/float64-get-low-word [github-issues-image]: http://img.shields.io/github/issues/math-io/float64-get-low-word.svg [github-issues-url]: https://github.com/math-io/float64-get-low-word/issues [tape]: https://github.com/substack/tape [istanbul]: https://github.com/gotwarlost/istanbul [testling]: https://ci.testling.com [compute-io]: https://github.com/compute-io/ [ieee754]: https://en.wikipedia.org/wiki/IEEE_754-1985