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 © 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