compute-lcm

Computes the least common multiple (lcm).


Keywords
compute.io, compute, computation, mathematics, math, least common multiple, lowest common multiple, smallest common multiple, lowest common denominator, lcm, lcd, discrete, arithmetic, array, integer, gcd, euclid
License
MIT
Install
npm install compute-lcm@1.1.2

Documentation

Least Common Multiple

NPM version Build Status Coverage Status Dependencies

Computes the least common multiple (lcm).

Note: the lcm is also known as the lowest common multiple or smallest common multiple and finds common use in calculating the lowest common denominator (lcd).

Installation

$ npm install compute-lcm

For use in the browser, use browserify.

Usage

var lcm = require( 'compute-lcm' );

lcm( a, b[, c,...,n] )

Computes the least common multiple (lcm) of two or more integers.

var val = lcm( 21, 6 );
// returns 42

var val = lcm( 21, 6, 126 );
// returns 126

lcm( arr[, clbk] )

Computes the least common multiple (lcm) of two or more integers.

var val = lcm( [21, 6] );
// returns 42

var val = lcm( [21, 6, 126] );
// returns 126

For object arrays, provide an accessor function for accessing array values.

var data = [
	['beep', 4],
	['boop', 8],
	['bap', 12],
	['baz', 16]
];

function getValue( d, i ) {
	return d[ 1 ];
}

var arr = lcm( arr, getValue );
// returns 48

Notes

  • If provided a single integer argument or an array with a length less than 2, the function returns null.

Examples

var lcm = require( 'compute-lcm' );

// Compute the lcm of random tuples...
var x, y, z, arr, val;
for ( var i = 0; i < 100; i++ ) {
	x = Math.round( Math.random()*50 );
	y = Math.round( Math.random()*50 );
	z = Math.round( Math.random()*50 );
	arr = [ x, y, z ];
	val = lcm( arr );
	console.log( arr, val );
}

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

$ node ./examples/index.js

Tests

Unit

Unit tests use the Mocha test framework with Chai assertions. 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

License

MIT license.

Copyright

Copyright © 2014-2015. Athan Reines.