<?php
/**
* This file was originally part of brick/math
*
* Copyright (c) 2013-present Benjamin Morel
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
* @link https://github.com/brick/math brick/math at GitHub
*/
declare(strict_types=1);
namespace Ramsey\Uuid\Math;
/**
* Specifies a rounding behavior for numerical operations capable of discarding
* precision.
*
* Each rounding mode indicates how the least significant returned digit of a
* rounded result is to be calculated. If fewer digits are returned than the
* digits needed to represent the exact numerical result, the discarded digits
* will be referred to as the discarded fraction regardless the digits'
* contribution to the value of the number. In other words, considered as a
* numerical value, the discarded fraction could have an absolute value greater
* than one.
*/
final class RoundingMode
{
/**
* Private constructor. This class is not instantiable.
*
* @codeCoverageIgnore
*/
private function __construct()
{
}
/**
* Asserts that the requested operation has an exact result, hence no
* rounding is necessary.
*/
public const UNNECESSARY = 0;
/**
* Rounds away from zero.
*
* Always increments the digit prior to a nonzero discarded fraction.
* Note that this rounding mode never decreases the magnitude of the
* calculated value.
*/
public const UP = 1;
/**
* Rounds towards zero.
*
* Never increments the digit prior to a discarded fraction (i.e.,
* truncates). Note that this rounding mode never increases the magnitude of
* the calculated value.
*/
public const DOWN = 2;
/**
* Rounds towards positive infinity.
*
* If the result is positive, behaves as for UP; if negative, behaves as for
* DOWN. Note that this rounding mode never decreases the calculated value.
*/
public const CEILING = 3;
/**
* Rounds towards negative infinity.
*
* If the result is positive, behave as for DOWN; if negative, behave as for
* UP. Note that this rounding mode never increases the calculated value.
*/
public const FLOOR = 4;
/**
* Rounds towards "nearest neighbor" unless both neighbors are equidistant,
* in which case round up.
*
* Behaves as for UP if the discarded fraction is >= 0.5; otherwise, behaves
* as for DOWN. Note that this is the rounding mode commonly taught at
* school.
*/
public const HALF_UP = 5;
/**
* Rounds towards "nearest neighbor" unless both neighbors are equidistant,
* in which case round down.
*
* Behaves as for UP if the discarded fraction is > 0.5; otherwise, behaves
* as for DOWN.
*/
public const HALF_DOWN = 6;
/**
* Rounds towards "nearest neighbor" unless both neighbors are equidistant,
* in which case round towards positive infinity.
*
* If the result is positive, behaves as for HALF_UP; if negative, behaves
* as for HALF_DOWN.
*/
public const HALF_CEILING = 7;
/**
* Rounds towards "nearest neighbor" unless both neighbors are equidistant,
* in which case round towards negative infinity.
*
* If the result is positive, behaves as for HALF_DOWN; if negative, behaves
* as for HALF_UP.
*/
public const HALF_FLOOR = 8;
/**
* Rounds towards the "nearest neighbor" unless both neighbors are
* equidistant, in which case rounds towards the even neighbor.
*
* Behaves as for HALF_UP if the digit to the left of the discarded fraction
* is odd; behaves as for HALF_DOWN if it's even.
*
* Note that this is the rounding mode that statistically minimizes
* cumulative error when applied repeatedly over a sequence of calculations.
* It is sometimes known as "Banker's rounding", and is chiefly used in the
* USA.
*/
public const HALF_EVEN = 9;
}