Numbers to Roman Numbers with php
arrays, numbers, php, roman-numerals
Solution
I found this code here: http://php.net/manual/en/function.base-convert.php
Optimized and prettified function:
/**
* @param int $number
* @return string
*/
function numberToRomanRepresentation($number) {
$map = array('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);
$returnValue = '';
while ($number > 0) {
foreach ($map as $roman => $int) {
if($number >= $int) {
$number -= $int;
$returnValue .= $roman;
break;
}
}
}
return $returnValue;
}
Problem
I need to transform ordinary numbers to Roman numerals with php and I have this code: ``` <?php function roman2number($roman){ $conv = array( array("letter" => 'I', "number" => 1), array("letter" => 'V', "number" => 5), array("letter" => 'X', "number" => 10), array("letter" => 'L', "number" => 50), array("letter" => 'C', "number" => 100), array("letter" => 'D', "number" => 500), array("letter" => 'M', "number" => 1000), array("letter" => 0, "number" => 0) ); $arabic = 0; $state = 0; $sidx = 0; $len = strlen($roman); while ($len >= 0) { $i = 0; $sidx = $len; while ($conv[$i]['number'] > 0) { if (strtoupper(@$roman[$sidx]) == $conv[$i]['letter']) { if ($state > $conv[$i]['number']) { $arabic -= $conv[$i]['number']; } else { $arabic += $conv[$i]['number']; $state = $conv[$i]['number']; } } $i++; } $len--; } return($arabic); } function number2roman($num,$isUpper=true) { $n = intval($num); $res = ''; /*** roman_numerals array ***/ $roman_numerals = array( 'M' => 1000, 'CM' => 900, 'D' => 500, 'CD' => 400, 'C' => 100, 'XC' => 90, 'L' => 50, 'XL' => 40, 'X' => 10, 'IX' => 9, 'V' => 5, 'IV' => 4, 'I' => 1 ); foreach ($roman_numerals as $roman => $number) { /*** divide to get matches ***/ $matches = intval($n / $number); /*** assign the roman char * $matches ***/ $res .= str_repeat($roman, $matches); /*** substract from the number ***/ $n = $n % $number; } /*** return the res ***/ if($isUpper) return $res; else return strtolower($res); } /* TEST */ echo $s=number2roman(6,true); echo "\n and bacK:\n"; echo roman2number($s); ?> ``` try this way but does not work: ``` echo $s=number2roman((.$row['id'].),true); echo "\n and bacK:\n"; echo roman2number($s); ``` the problem is that I need to change numbers are readings of my sql database and do not know how to, from and through.