cospi

Computes the cosine of a number times π.

Installation

$ npm install math-cospi

Usage

var cospi = require( 'math-cospi' );

cospi( x )

Computes cos(πx) more accurately than cos(pi*x), especially for large x.

var y = cospi( 0 );
// returns 1

y = cospi( 0.5 );
// returns 0

y = cospi( 0.1 );
// returns ~0.951

Examples

var linspace = require( 'compute-linspace' );
var cospi = require( 'math-cospi' );

var x = linspace( -100, 100, 100 );
var i;

for ( i = 0; i < x.length; i++ ) {
	console.log( cospi( x[ i ] ) );
}

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.