math-float64-signbit

Returns a boolean indicating if the sign bit for a double-precision floating-point number is on (true) or off (false).

Usage no npm install needed!

<script type="module">
  import mathFloat64Signbit from 'https://cdn.skypack.dev/math-float64-signbit';
</script>

README

signbit

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Returns a boolean indicating if the sign bit for a double-precision floating-point number is on (true) or off (false).

Installation

$ npm install math-float64-signbit

Usage

var signbit = require( 'math-float64-signbit' );

signbit( x )

Returns a boolean indicating if the sign bit for a double-precision floating-point number is on (true) or off (false).

var bool = signbit( 4 );
// returns false

bool = signbit( -9.14e-307 );
// returns true

bool = signbit( 0 );
// returns false

bool = signbit( -0 );
// returns true

Examples

var signbit = require( 'math-float64-signbit' );

var sign;
var x;
var i;

for ( i = 0; i < 100; i++ ) {
    x = Math.random()*100 - 50;
    sign = signbit( x );
    sign = ( sign ) ? 'true' : 'false';
    console.log( 'x: %d. signbit: %s.', x, sign );
}

To run the example code from the top-level application directory,

$ node ./examples/index.js

Tests

Unit

This repository uses tape for unit tests. To run the tests, execute the following command in the top-level application directory:

$ make test

All new feature development should have corresponding unit tests to validate correct functionality.

Test Coverage

This repository uses Istanbul as its code coverage tool. To generate a test coverage report, execute the following command in the top-level application directory:

$ make test-cov

Istanbul creates a ./reports/coverage directory. To access an HTML version of the report,

$ make view-cov

Browser Support

This repository uses Testling for browser testing. To run the tests in a (headless) local web browser, execute the following command in the top-level application directory:

$ make test-browsers

To view the tests in a local web browser,

$ make view-browser-tests

License

MIT license.

Copyright

Copyright © 2016. The Compute.io Authors.