1.0.1 • Published 8 years ago

math-float64-to-binary-string v1.0.1

Weekly downloads
2
License
MIT
Repository
github
Last release
8 years ago

Binary String

NPM version Build Status Coverage Status Dependencies

Returns a string giving the literal bit representation of a double-precision floating-point number.

Installation

$ npm install math-float64-to-binary-string

Usage

var binaryString = require( 'math-float64-to-binary-string' );

binaryString( x )

Returns a string giving the literal bit representation of a double-precision floating-point number.

var str = binaryString( 4 );
// returns '0100000000010000000000000000000000000000000000000000000000000000'

str = binaryString( Math.PI );
// returns '0100000000001001001000011111101101010100010001000010110100011000'

str = binaryString( -1e308 );
// returns '1111111111100001110011001111001110000101111010111100100010100000'

The function handles subnormals.

str = binaryString( -3.14e-320 );
// returns '1000000000000000000000000000000000000000000000000001100011010011'

str = binaryString( 5e-324 );
// returns '0000000000000000000000000000000000000000000000000000000000000001'

The function handles special values.

str = binaryString( 0 );
// returns '0000000000000000000000000000000000000000000000000000000000000000'

str = binaryString( -0 );
// returns '1000000000000000000000000000000000000000000000000000000000000000'

str = binaryString( NaN );
// returns '0111111111111000000000000000000000000000000000000000000000000000'

str = binaryString( Number.POSITIVE_INFINITY );
// returns '0111111111110000000000000000000000000000000000000000000000000000'

str = binaryString( Number.NEGATIVE_INFINITY );
// returns '1111111111110000000000000000000000000000000000000000000000000000'

Examples

var round = require( 'math-round' );
var pow = require( 'math-power' );
var smallest = require( 'const-smallest-float64' );
var binaryString = require( 'math-float64-to-binary-string' );

var frac;
var sign;
var exp;
var b;
var x;
var i;

// Convert random numbers to literal bit representations...
for ( i = 0; i < 100; i++ ) {
	if ( Math.random() < 0.5 ) {
		sign = -1;
	} else {
		sign = 1;
	}
	frac = Math.random() * 10;
	exp = round( Math.random()*100 );
	if ( Math.random() < 0.5 ) {
		exp = -exp;
	}
	x = sign * frac * pow( 2, exp );
	b = binaryString( x );
	console.log( b );
}

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.