Roman numerals

Readme.md

Roman Numerals

Installation

Download composer.phar from https://getcomposer.org/

curl -sS https://getcomposer.org/installer | php

Install dependencies

php composer.phar install

Usage

Run unit tests

vendor/bin/phpunit RomanNumeralsTest.php

composer.json

{
    "require-dev": {
        "phpunit/phpunit": "4.*"
    },
    "autoload": {
        "files": ["RomanNumerals.php"]
    }
}

RomanNumerals.php

<?php

class RomanNumerals
{
    public function arabicToRoman($arabicNumber)
    {
        $roman = '';

        $chars = [
            'M'  => 1000,
            'CM' => 900,
            'D'  => 500,
            'CD' => 400,
            'C'  => 100,
            'XC' => 90,
            'L'  => 50,
            'XL' => 40,
            'X'  => 10,
            'IX' => 9,
            'V'  => 5,
            'IV' => 4,
            'I'  => 1,
        ];

        foreach ($chars as $c => $n) {
            while ($arabicNumber >= $n) {
                $roman .= $c;
                $arabicNumber -= $n;
            }
        }

        return $roman;
    }
} 

RomanNumeralsTest.php

<?php

// Composer genereated autoloader
require __DIR__.'/vendor/autoload.php';

class RomanNumeralsTest extends PHPUnit_Framework_TestCase
{
    public function testDataProvider()
    {
        return array(
            array(1, 'I'),
            array(2, 'II'),
            array(3, 'III'),
            array(4, 'IV'),
            array(5, 'V'),
            array(6, 'VI'),
            array(7, 'VII'),
            array(8, 'VIII'),
            array(9, 'IX'),
            array(10, 'X'),
            array(12, 'XII'),
            array(66, 'LXVI'),
            array(1970, 'MCMLXX'),
            array(2000, 'MM'),
        );
    }

    /**
     * @dataProvider testDataProvider
     */
    public function testArabicToRoman1($number, $result)
    {
        $Roman = new RomanNumerals();
        $this->assertEquals($result, $Roman->arabicToRoman($number));
    }
}