Subversion-Projekte lars-tiefland.laravel_shop

<?php

/**
 * This file is part of the Nette Framework (https://nette.org)
 * Copyright (c) 2004 David Grudl (https://davidgrudl.com)
 */

declare(strict_types=1);

namespace Nette\Utils;

use Nette;


/**
 * Floating-point numbers comparison.
 */
class Floats
{
        use Nette\StaticClass;

        private const Epsilon = 1e-10;


        public static function isZero(float $value): bool
        {
                return abs($value) < self::Epsilon;
        }


        public static function isInteger(float $value): bool
        {
                return abs(round($value) - $value) < self::Epsilon;
        }


        /**
         * Compare two floats. If $a < $b it returns -1, if they are equal it returns 0 and if $a > $b it returns 1
         * @throws \LogicException if one of parameters is NAN
         */
        public static function compare(float $a, float $b): int
        {
                if (is_nan($a) || is_nan($b)) {
                        throw new \LogicException('Trying to compare NAN');

                } elseif (!is_finite($a) && !is_finite($b) && $a === $b) {
                        return 0;
                }

                $diff = abs($a - $b);
                if (($diff < self::Epsilon || ($diff / max(abs($a), abs($b)) < self::Epsilon))) {
                        return 0;
                }

                return $a < $b ? -1 : 1;
        }


        /**
         * Returns true if $a = $b
         * @throws \LogicException if one of parameters is NAN
         */
        public static function areEqual(float $a, float $b): bool
        {
                return self::compare($a, $b) === 0;
        }


        /**
         * Returns true if $a < $b
         * @throws \LogicException if one of parameters is NAN
         */
        public static function isLessThan(float $a, float $b): bool
        {
                return self::compare($a, $b) < 0;
        }


        /**
         * Returns true if $a <= $b
         * @throws \LogicException if one of parameters is NAN
         */
        public static function isLessThanOrEqualTo(float $a, float $b): bool
        {
                return self::compare($a, $b) <= 0;
        }


        /**
         * Returns true if $a > $b
         * @throws \LogicException if one of parameters is NAN
         */
        public static function isGreaterThan(float $a, float $b): bool
        {
                return self::compare($a, $b) > 0;
        }


        /**
         * Returns true if $a >= $b
         * @throws \LogicException if one of parameters is NAN
         */
        public static function isGreaterThanOrEqualTo(float $a, float $b): bool
        {
                return self::compare($a, $b) >= 0;
        }
}