<?php
/* math class
 * (C) 2006 Julian von Mendel (http://derjulian.net)
 * License: LGPL
 */

class math
{
    public static function greatestcommondivisor($a,$b=False)
    { /* calculates the gcd by using the euclidean algorithm */

        if (is_array($a))
        {
            $gcd = reset($a);
            foreach($a as $x)
                $gcd = self::greatestcommondivisor($gcd,$x);
            return $gcd;
        }

        if ($b == 0) return $a;
        return self::greatestcommondivisor($b, $a % $b);
    }

    public static function leastcommonmultiple($a,$b=False)
    { /* calculates the lcm by using the gcd */

        if (is_array($a))
        {
            $lcm = reset($a);
            foreach($a as $x)
                $lcm = self::leastcommonmultiple($lcm,$x);
            return $lcm;
        }

        return $a * $b / self::greatestcommondivisor($a, $b);
    }

    public static function degree2radian($degrees,$retfraction=True)
    { /* calculates the radian out of an arc degree; if $retfraction is set to
       * False, a decimal number is returned instead of a fraction object which
       * has to be multiplied with pi.
       */

        $f = new fraction;
        $f->setdecimal($degrees);
        $x_pi = fraction::division(array($f,180));
        $x_pi->cancel();
        if ($retfraction) return $x_pi;
        return round($x_pi->getdecimal(10)*M_PI,10);
    }

    public static function radian2degree($radian)
    { /* calculates the arc degree out of a radian */

        return $radian*180/M_PI;
    }
}
?>