doc.silverstripe.org/sapphire/thirdparty/Zend/Locale/Math/PhpMath.php
2011-04-10 21:53:26 +00:00

248 lines
8.1 KiB
PHP

<?php
/**
* Zend Framework
*
* LICENSE
*
* This source file is subject to the new BSD license that is bundled
* with this package in the file LICENSE.txt.
* It is also available through the world-wide-web at this URL:
* http://framework.zend.com/license/new-bsd
* If you did not receive a copy of the license and are unable to
* obtain it through the world-wide-web, please send an email
* to license@zend.com so we can send you a copy immediately.
*
* @category Zend
* @package Zend_Locale
* @copyright Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
* @version $Id: PhpMath.php 12514 2008-11-10 16:30:24Z matthew $
*/
/**
* Utility class for proxying math function to bcmath functions, if present,
* otherwise to PHP builtin math operators, with limited detection of overflow conditions.
* Sampling of PHP environments and platforms suggests that at least 80% to 90% support bcmath.
* This file should only be loaded for the 10% to 20% lacking access to the bcmath extension.
*
* @category Zend
* @package Zend_Locale
* @copyright Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
class Zend_Locale_Math_PhpMath extends Zend_Locale_Math
{
public static function disable()
{
self::$_bcmathDisabled = true;
self::$add = array('Zend_Locale_Math_PhpMath', 'Add');
self::$sub = array('Zend_Locale_Math_PhpMath', 'Sub');
self::$pow = array('Zend_Locale_Math_PhpMath', 'Pow');
self::$mul = array('Zend_Locale_Math_PhpMath', 'Mul');
self::$div = array('Zend_Locale_Math_PhpMath', 'Div');
self::$comp = array('Zend_Locale_Math_PhpMath', 'Comp');
self::$sqrt = array('Zend_Locale_Math_PhpMath', 'Sqrt');
self::$mod = array('Zend_Locale_Math_PhpMath', 'Mod');
self::$scale = array('Zend_Locale_Math_PhpMath', 'Scale');
self::$defaultScale = 0;
self::$defaultPrecision = 1;
}
public static $defaultScale;
public static $defaultPrecision;
public static function Add($op1, $op2, $scale = null)
{
if ($scale === null) {
$scale = Zend_Locale_Math_PhpMath::$defaultScale;
$precision = Zend_Locale_Math_PhpMath::$defaultPrecision;
} else {
$precision = pow(10, -$scale);
}
if (empty($op1)) {
$op1 = 0;
}
$op1 = self::normalize($op1);
$op2 = self::normalize($op2);
$result = $op1 + $op2;
if (is_infinite($result) or (abs($result - $op2 - $op1) > $precision)) {
require_once 'Zend/Locale/Math/Exception.php';
throw new Zend_Locale_Math_Exception("addition overflow: $op1 + $op2 != $result", $op1, $op2, $result);
}
return self::round(self::normalize($result), $scale);
}
public static function Sub($op1, $op2, $scale = null)
{
if ($scale === null) {
$scale = Zend_Locale_Math_PhpMath::$defaultScale;
$precision = Zend_Locale_Math_PhpMath::$defaultPrecision;
} else {
$precision = pow(10, -$scale);
}
if (empty($op1)) {
$op1 = 0;
}
$op1 = self::normalize($op1);
$op2 = self::normalize($op2);
$result = $op1 - $op2;
if (is_infinite($result) or (abs($result + $op2 - $op1) > $precision)) {
require_once 'Zend/Locale/Math/Exception.php';
throw new Zend_Locale_Math_Exception("subtraction overflow: $op1 - $op2 != $result", $op1, $op2, $result);
}
return self::round(self::normalize($result), $scale);
}
public static function Pow($op1, $op2, $scale = null)
{
if ($scale === null) {
$scale = Zend_Locale_Math_PhpMath::$defaultScale;
}
$op1 = self::normalize($op1);
$op2 = self::normalize($op2);
// BCMath extension doesn't use decimal part of the power
// Provide the same behavior
$op2 = ($op2 > 0) ? floor($op2) : ceil($op2);
$result = pow($op1, $op2);
if (is_infinite($result) or is_nan($result)) {
require_once 'Zend/Locale/Math/Exception.php';
throw new Zend_Locale_Math_Exception("power overflow: $op1 ^ $op2", $op1, $op2, $result);
}
return self::round(self::normalize($result), $scale);
}
public static function Mul($op1, $op2, $scale = null)
{
if ($scale === null) {
$scale = Zend_Locale_Math_PhpMath::$defaultScale;
}
if (empty($op1)) {
$op1 = 0;
}
$op1 = self::normalize($op1);
$op2 = self::normalize($op2);
$result = $op1 * $op2;
if (is_infinite($result) or is_nan($result)) {
require_once 'Zend/Locale/Math/Exception.php';
throw new Zend_Locale_Math_Exception("multiplication overflow: $op1 * $op2 != $result", $op1, $op2, $result);
}
return self::round(self::normalize($result), $scale);
}
public static function Div($op1, $op2, $scale = null)
{
if ($scale === null) {
$scale = Zend_Locale_Math_PhpMath::$defaultScale;
}
if (empty($op2)) {
require_once 'Zend/Locale/Math/Exception.php';
throw new Zend_Locale_Math_Exception("can not divide by zero", $op1, $op2, null);
}
if (empty($op1)) {
$op1 = 0;
}
$op1 = self::normalize($op1);
$op2 = self::normalize($op2);
$result = $op1 / $op2;
if (is_infinite($result) or is_nan($result)) {
require_once 'Zend/Locale/Math/Exception.php';
throw new Zend_Locale_Math_Exception("division overflow: $op1 / $op2 != $result", $op1, $op2, $result);
}
return self::round(self::normalize($result), $scale);
}
public static function Sqrt($op1, $scale = null)
{
if ($scale === null) {
$scale = Zend_Locale_Math_PhpMath::$defaultScale;
}
if (empty($op1)) {
$op1 = 0;
}
$op1 = self::normalize($op1);
$result = sqrt($op1);
if (is_nan($result)) {
return NULL;
}
return self::round(self::normalize($result), $scale);
}
public static function Mod($op1, $op2)
{
if (empty($op1)) {
$op1 = 0;
}
if (empty($op2)) {
return NULL;
}
$op1 = self::normalize($op1);
$op2 = self::normalize($op2);
if ((int)$op2 == 0) {
return NULL;
}
$result = $op1 % $op2;
if (is_nan($result) or (($op1 - $result) % $op2 != 0)) {
require_once 'Zend/Locale/Math/Exception.php';
throw new Zend_Locale_Math_Exception("modulus calculation error: $op1 % $op2 != $result", $op1, $op2, $result);
}
return self::normalize($result);
}
public static function Comp($op1, $op2, $scale = null)
{
if ($scale === null) {
$scale = Zend_Locale_Math_PhpMath::$defaultScale;
}
if (empty($op1)) {
$op1 = 0;
}
$op1 = self::normalize($op1);
$op2 = self::normalize($op2);
if ($scale <> 0) {
$op1 = self::round($op1, $scale);
$op2 = self::round($op2, $scale);
} else {
$op1 = ($op1 > 0) ? floor($op1) : ceil($op1);
$op2 = ($op2 > 0) ? floor($op2) : ceil($op2);
}
if ($op1 > $op2) {
return 1;
} else if ($op1 < $op2) {
return -1;
}
return 0;
}
public static function Scale($scale)
{
if ($scale > 9) {
require_once 'Zend/Locale/Math/Exception.php';
throw new Zend_Locale_Math_Exception("can not scale to precision $scale", $scale, null, null);
}
self::$defaultScale = $scale;
self::$defaultPrecision = pow(10, -$scale);
return true;
}
}
Zend_Locale_Math_PhpMath::disable(); // disable use of bcmath functions