added Fraction

composer.json

@@ -10,6 +10,7 @@
 	},
 	"require": {
 		"ext-bcmath": "*",
+		"ext-ctype": "*",
 		"php": ">=8.2"
 	},
 	"require-dev": {

src/Simplex/Math/Fraction.php

@@ -0,0 +1,235 @@
+<?php
+
+declare(strict_types = 1);
+
+/**
+ * This file is part of the Simplex-Calculator library
+ *
+ * Copyright (c) 2014 Petr Kessler (https://kesspess.cz)
+ *
+ * @license  MIT
+ * @link     https://github.com/uestla/Simplex-Calculator
+ */
+
+namespace Simplex\Math;
+
+use Simplex\DivisionByZeroException;
+use Simplex\ScientificFloatException;
+use Simplex\NonNumericArgumentException;
+
+
+final readonly class Fraction implements \Stringable
+{
+	public string $n;
+	public string $d;
+
+
+	public function __construct(string $n, string $d = '1')
+	{
+		$n = self::processNumber($n);
+		$d = self::processNumber($d);
+
+		if ($d === '0') {
+			throw new DivisionByZeroException;
+		}
+
+		if ($d === '-1') {
+			$n = mul($n, '-1');
+			$d = '1';
+
+		} elseif ($d !== '1') {
+			$gcd = gcd($n, $d);
+
+			if ($gcd !== '1') {
+				$n = div($n, $gcd);
+				$d = div($d, $gcd);
+			}
+
+			if (isNegative($d)) {
+				$n = mul($n, '-1');
+				$d = mul($d, '-1');
+			}
+		}
+
+		$this->n = $n;
+		$this->d = $d;
+	}
+
+
+	public static function create(self|string|int|float $a): self
+	{
+		if ($a instanceof self) {
+			return $a;
+		}
+
+		[$n, $d] = self::factoryParts($a);
+		return new self($n, $d);
+	}
+
+
+	/** a/b + c/d = (ad + bc)/bd */
+	public function add(self $a): self
+	{
+		return new self(
+			add(
+				mul($this->n, $a->d),
+				mul($this->d, $a->n),
+			),
+			mul($this->d, $a->d),
+		);
+	}
+
+
+	/** a/b - c/d = (ad - bc)/bd */
+	public function subtract(self $a): self
+	{
+		return new self(
+			sub(
+				mul($this->n, $a->d),
+				mul($this->d, $a->n),
+			),
+			mul($this->d, $a->d),
+		);
+	}
+
+
+	/** (a/b)(c/d) = (ac/bd) */
+	public function multiply(self|string $a): self
+	{
+		if (is_string($a)) {
+			$a = self::processNumber($a);
+
+			return new self(
+				mul($this->n, $a),
+				$this->d,
+			);
+		}
+
+		return new self(
+			mul($this->n, $a->n),
+			mul($this->d, $a->d),
+		);
+	}
+
+
+	/** (a/b)/(c/d) = ad/bc */
+	public function divide(self $a): self
+	{
+		return new self(
+			mul($this->n, $a->d),
+			mul($this->d, $a->n),
+		);
+	}
+
+
+	public function abs(): self
+	{
+		return new self(
+			abs($this->n),
+			$this->d,
+		);
+	}
+
+
+	public function isEqualTo(self|string $a): bool
+	{
+		if (is_string($a)) {
+			$a = self::processNumber($a);
+			return $this->d === '1' && $this->n === $a;
+		}
+
+		return $this->n === $a->n && $this->d === $a->d;
+	}
+
+
+	public function isPositive(): bool
+	{
+		return $this->n !== '0' && !$this->isNegative();
+	}
+
+
+	public function isNegative(): bool
+	{
+		return isNegative($this->n);
+	}
+
+
+	public function isLowerThan(Fraction $a): bool
+	{
+		return comp(
+			mul($this->n, $a->d),
+			mul($a->n, $this->d),
+
+		) === -1;
+	}
+
+
+	public function toNumericString(int $precision): string
+	{
+		return round(div($this->n, $this->d, $precision + 1), $precision);
+	}
+
+
+	public function toString(): string
+	{
+		return $this->n . ($this->d === '1' ? '' : '/' . $this->d);
+	}
+
+
+	public function __toString(): string
+	{
+		return $this->toString();
+	}
+
+
+	private static function processNumber(string $n): string
+	{
+		$abs = abs($n);
+
+		if (!ctype_digit($abs)) {
+			throw new NonNumericArgumentException($n);
+		}
+
+		$trimmed = ltrim($abs, '0');
+
+		return ($abs === $n ? '' : '-')
+			. ($trimmed === '' ? '0' : $trimmed);
+	}
+
+
+	/** @return array{string, string} */
+	private static function factoryParts(string|int|float $a): array
+	{
+		if (!is_numeric($a)) {
+			throw new NonNumericArgumentException($a);
+		}
+
+		$n = (string) $a;
+		$d = '1';
+
+		$expPos = stripos($n, 'e'); // exponent
+		$dotPos = strpos($n, '.'); // decimal point
+
+		if ($expPos !== false && $dotPos !== false) {
+			throw new ScientificFloatException;
+		}
+
+		if ($expPos !== false) {
+			$exp = substr($n, $expPos + 1);
+			$n = substr($n, 0, $expPos);
+
+			if (isNegative($exp)) {
+				$d = '1' . str_repeat('0', (int) substr($exp, 1));
+
+			} else {
+				$n .= str_repeat('0', (int) $exp);
+			}
+
+		} elseif ($dotPos !== false) {
+			$d = '1' . str_repeat('0', strlen($n) - $dotPos - 1);
+			$n = str_replace('.', '', $n);
+		}
+
+		return [$n, $d];
+	}
+}

src/Simplex/exceptions.php

@@ -23,5 +23,32 @@ public function __construct()
 }
 
 
+final class DivisionByZeroException extends SimplexException
+{
+	public function __construct()
+	{
+		parent::__construct('Division by zero.');
+	}
+}
+
+
+final class NonNumericArgumentException extends SimplexException
+{
+	public function __construct(string $s)
+	{
+		parent::__construct(sprintf('Non-numeric argument "%s".', $s));
+	}
+}
+
+
+final class ScientificFloatException extends SimplexException
+{
+	public function __construct()
+	{
+		parent::__construct('Floats with scientific notation are not supported.');
+	}
+}
+
+
 abstract class SimplexException extends \Exception
 {}

src/Simplex/simplex.php

@@ -16,3 +16,4 @@
 
 require_once __DIR__ . '/exceptions.php';
 require_once __DIR__ . '/Math/math.php';
+require_once __DIR__ . '/Math/Fraction.php';