<?php
	// $Id: bcadd.php,v 1.4 2005/04/10 12:47:20 rufustfirefly Exp $
	// $Author: rufustfirefly $

// File: bcadd
//
//	This function is meant to be a drop-in replacement for those
//	people who don't have bcmath functionality in their PHP
//	distribution. It probably has problems, and the best solution
//	is to build yourself a version with bcmath support. Barring
//	this, you can use this hack. (Jeff)
//
// 	A regex for exponential numbers is
//	[-+]?([0-9]*\.)?[0-9]+([eE][-+]?[0-9]+)?

// Function: bcadd
//
//	Provides bcadd functionality (from bcmath extension) without
//	having to load bcmath PHP extension.
//
// Parameters:
//
//	$left - First number to add.
//
//	$right - Second number to add.
//
//	$scale - Number of digits of precision desired after the
//	decimal point. 0 will produce an integer.
//
// Returns:
//
//	left and right added together with a precision of scale.
//
function bcadd ($left, $right, $scale) {
	// Deal with numbers smaller than $scale
	$_left = ($left < pow(10, -$scale)) ? 0 : $left;
	$_right = ($right < pow(10, -$scale)) ? 0 : $right;

	// first add the two numbers
	$sum = (double)($_left + $_right);

	// check for a dot in the number
	if (strpos($sum, ".") === false) {
		// not found, integer
		$int_part = $sum;
		$real_part = 0;
	} else {
		// if not, we split
		list ($int_part, $real_part) = explode (".", $sum);
	} // end checking for a dot

	// handle scale of 0
	if ($scale == 0) return $int_part;

	// handle real parts that need more precision
	if ($scale > strlen($real_part)) {
		for ($i=0;$i<=($scale - strlen($real_part));$i++)
			$real_part .= "0";
	} // end checking for more precision needed

	// return built string
	return $int_part . "." . substr($real_part, 0, $scale);
} // end function bcadd

?>