Copysign
Returns a double-precision floating-point number with the magnitude of
x
and the sign ofy
.
Installation
$ npm install math-float64-copysign
Usage
var copysign = ;
copysign( x, y )
Returns a double-precision floating-point number with the magnitude of x
and the sign of y
.
var z = ;// returns 3.14z = ;// returns -3.14z = ;// returns -1z = ;// returns -3.14z = ;// returns 0
Notes
- According to the IEEE754 standard, a
NaN
has a biased exponent equal to2047
, a significand greater than0
, and a sign bit equal to either1
or0
. In which case,NaN
may not correspond to just one but many binary representations. Accordingly, care should be taken to ensure thaty
is notNaN
, else behavior may be indeterminate.
Examples
var copysign = ;var x;var y;var z;var i;// Generate random double-precision floating-point numbers `x` and `y` and copy the sign of `y` to `x`...for i = 0; i < 100; i++x = Math*100 - 50;y = Math*10 - 5;z = ;console;
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
Copyright
Copyright © 2016. The Compute.io Authors.