Format number or string as a float

money_float.php

<?php

/**
* Take a number or numerical string and format as float
* Supports US and UK formats. Designed for money but will work with other formats as well.
* @param mixed $amount
* @param int $decimal_places
* @param int $round_mode
* @return float
*/
function money_float($amount, $decimal_places=2, $round_mode=PHP_ROUND_HALF_UP){
	if(empty($amount)){
		$amount = 0;
	}
	else if(is_object($amount)){
		$amount = (string)$amount;
	}
	if(is_string($amount)){
		$amount = trim($amount, "\$£€¥ \t\n\r\0\x0B");
		// Strip thousands separator
		$comma = 0+strrpos($amount, ',');
		$period = 0+strrpos($amount, '.');
		$len = strlen($amount);
		// Strip thousands separator
		if($period || $comma){
			if($comma && ($period > $comma || (!$period && ($len - $comma -1) % 3 == 0))){
				$amount = str_replace(',','',$amount);
			}
			else if($period && ($comma > $period || (!$comma && ($len - $period -1) % 3 == 0))){
				$amount = str_replace('.','',$amount);
			}
		}
		$amount = floatval($amount);
	}
	return round(number_format($amount, $decimal_places+1, '.', ''), $decimal_places);
}