Computes the differences between adjacent elements in an array of values.
npm install compute-diffdiff
===
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> Computes the differences between adjacent elements in an array of values.
`` bash`
$ npm install compute-diff
For use in the browser, use browserify.
To use the module,
` javascript`
var diff = require( 'compute-diff' );
#### diff( arr )
Computes the differences between adjacent array values.
` javascript
var data = [ 1, 3, 2, 10, 5 ];
var vals = diff( data );
// returns [ -2, 1, -8, 5 ]
`
Note: the returned array will have a length which is one less than the original array; i.e., if arr.length = 10, then diff( arr ).length = 9.
` javascript
var diff = require( 'compute-diff' );
var data = new Array( 100 );
for ( var i = 0; i < data.length; i++ ) {
data[ i ] = Math.round( Math.random() * 100 );
}
console.log( diff( data ) );
`
To run the example code from the top-level application directory,
` bash`
$ node ./examples/index.js
Unit tests use the Mocha test framework with Chai assertions. 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.
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:
` bash`
$ make test-cov
Istanbul creates a ./reports/coverage directory. To access an HTML version of the report,
` bash``
$ make view-cov
---
Copyright © 2014. Athan Reines.
[npm-image]: http://img.shields.io/npm/v/compute-diff.svg
[npm-url]: https://npmjs.org/package/compute-diff
[travis-image]: http://img.shields.io/travis/compute-io/diff/master.svg
[travis-url]: https://travis-ci.org/compute-io/diff
[coveralls-image]: https://img.shields.io/coveralls/compute-io/diff/master.svg
[coveralls-url]: https://coveralls.io/r/compute-io/diff?branch=master
[dependencies-image]: http://img.shields.io/david/compute-io/diff.svg
[dependencies-url]: https://david-dm.org/compute-io/diff
[dev-dependencies-image]: http://img.shields.io/david/dev/compute-io/diff.svg
[dev-dependencies-url]: https://david-dm.org/dev/compute-io/diff
[github-issues-image]: http://img.shields.io/github/issues/compute-io/diff.svg
[github-issues-url]: https://github.com/compute-io/diff/issues