Bcmath (#115)

phpfui · web-flow · commit a944fe4e5631 · 2022-06-01T18:11:51.000-04:00
* Add useBCMath

* Support for % operator (mod)
diff --git a/README.md b/README.md
@@ -3,7 +3,7 @@
 # A simple and extensible math expressions calculator
 
 ## Features:
-* Built in support for +, -, *, / and power (^) operators
+* Built in support for +, -, *, %, / and power (^) operators
 * Paratheses () and arrays [] are fully supported
 * Logical operators (==, !=, <, <, >=, <=, &&, ||)
 * Built in support for most PHP math functions
@@ -101,7 +101,7 @@ $executor->calculate('avarage(1, 3, 4, 8)'); // 4
 ```
 
 ## Operators:
-Default operators: `+ - * / ^`
+Default operators: `+ - * / % ^`
 
 Add custom operator to executor:
 
@@ -111,7 +111,7 @@ use NXP\Classes\Operator;
 $executor->addOperator(new Operator(
     '%', // Operator sign
     false, // Is right associated operator
-    170, // Operator priority
+    180, // Operator priority
     function (&$stack)
     {
        $op2 = array_pop($stack);
@@ -189,6 +189,10 @@ $calculator->setVarNotFoundHandler(
 );
 ```
 
+## Floating Point BCMath Support
+By default, `MathExecutor` uses PHP floating point math, but if you need a fixed precision, call **useBCMath()**. Precision defaults to 2 decimal points, or pass the required number.
+`WARNING`: Functions may return a PHP floating point number.  By doing the basic math functions on the results, you will get back a fixed number of decimal points. Use a plus sign in from of any stand alone function to return the proper number of decimal places.
+
 ## Division By Zero Support:
 Division by zero throws a `\NXP\Exception\DivisionByZeroException` by default
 ```php
diff --git a/src/NXP/MathExecutor.php b/src/NXP/MathExecutor.php
@@ -263,7 +263,7 @@ public function removeVars() : self
      *
      * @return array<Operator> of operator class names
      */
-    public function getOperators()
+    public function getOperators() : array
     {
         return $this->operators;
     }
@@ -279,6 +279,18 @@ public function getFunctions() : array
         return $this->functions;
     }
 
+    /**
+     * Remove a specific operator
+     *
+     * @return array<Operator> of operator class names
+     */
+    public function removeOperator(string $operator) : self
+    {
+        unset($this->operators[$operator]);
+
+        return $this;
+    }
+
     /**
      * Set division by zero returns zero instead of throwing DivisionByZeroException
      */
@@ -301,16 +313,39 @@ public function getCache() : array
     /**
      * Clear token's cache
      */
-    public function clearCache() : void
+    public function clearCache() : self
     {
         $this->cache = [];
+
+        return $this;
+    }
+
+    public function useBCMath(int $scale = 2) : self
+    {
+      \bcscale($scale);
+      $this->addOperator(new Operator('+', false, 170, static fn($a, $b) => \bcadd("{$a}", "{$b}")));
+      $this->addOperator(new Operator('-', false, 170, static fn($a, $b) => \bcsub("{$a}", "{$b}")));
+      $this->addOperator(new Operator('uNeg', false, 200, static fn($a) => \bcsub('0.0', "{$a}")));
+      $this->addOperator(new Operator('*', false, 180, static fn($a, $b) => \bcmul("{$a}", "{$b}")));
+      $this->addOperator(new Operator('/', false, 180, static function($a, $b) {
+          /** @todo PHP8: Use throw as expression -> static fn($a, $b) => 0 == $b ? throw new DivisionByZeroException() : $a / $b */
+          if (0 == $b) {
+              throw new DivisionByZeroException();
+          }
+
+          return \bcdiv("{$a}", "{$b}");
+      }));
+      $this->addOperator(new Operator('^', true, 220, static fn($a, $b) => \bcpow("{$a}", "{$b}")));
+      $this->addOperator(new Operator('%', false, 180, static fn($a, $b) => \bcmod("{$a}", "{$b}")));
+
+      return $this;
     }
 
     /**
      * Set default operands and functions
      * @throws ReflectionException
      */
-    protected function addDefaults() : void
+    protected function addDefaults() : self
     {
         foreach ($this->defaultOperators() as $name => $operator) {
             [$callable, $priority, $isRightAssoc] = $operator;
@@ -323,6 +358,8 @@ protected function addDefaults() : void
 
         $this->onVarValidation = [$this, 'defaultVarValidation'];
         $this->variables = $this->defaultVars();
+
+        return $this;
     }
 
     /**
@@ -352,6 +389,7 @@ static function($a, $b) { /** @todo PHP8: Use throw as expression -> static fn($
             false
           ],
           '^' => [static fn($a, $b) => \pow($a, $b), 220, true],
+          '%' => [static fn($a, $b) => $a % $b, 180, false],
           '&&' => [static fn($a, $b) => $a && $b, 100, false],
           '||' => [static fn($a, $b) => $a || $b, 90, false],
           '==' => [static fn($a, $b) => \is_string($a) || \is_string($b) ? 0 == \strcmp($a, $b) : $a == $b, 140, false],
diff --git a/tests/MathTest.php b/tests/MathTest.php
@@ -113,6 +113,7 @@ public function providerExpressions()
           ['tanh(1.5)'],
 
           ['0.1 + 0.2'],
+          ['0.1 + 0.2 - 0.3'],
           ['1 + 2'],
 
           ['0.1 - 0.2'],
@@ -246,7 +247,246 @@ public function providerExpressions()
           ['max(1,2,4.9,3)'],
           ['min(1,2,4.9,3)'],
           ['max([1,2,4.9,3])'],
-          ['min([1,2,4.9,3])']
+          ['min([1,2,4.9,3])'],
+
+          ['4 % 4'],
+          ['7 % 4'],
+          ['99 % 4'],
+          ['123 % 7'],
+        ];
+    }
+
+    /**
+     * @dataProvider bcMathExpressions
+     */
+    public function testBCMathCalculating(string $expression, string $expected = '') : void
+    {
+        $calculator = new MathExecutor();
+        $calculator->useBCMath();
+
+        if ('' === $expected)
+        {
+            $expected = $expression;
+        }
+
+        /** @var float $phpResult */
+        eval('$phpResult = ' . $expected . ';');
+
+        try {
+            $result = $calculator->execute($expression);
+        } catch (Exception $e) {
+            $this->fail(\sprintf('Exception: %s (%s:%d), expression was: %s', \get_class($e), $e->getFile(), $e->getLine(), $expression));
+        }
+        $this->assertEquals($phpResult, $result, "Expression was: {$expression}");
+    }
+
+    /**
+     * Expressions data provider
+     *
+     * Most tests can go in here.  The idea is that each expression will be evaluated by MathExecutor and by PHP with eval.
+     * The results should be the same.  If they are not, then the test fails.  No need to add extra test unless you are doing
+     * something more complex and not a simple mathmatical expression.
+     */
+    public function bcMathExpressions()
+    {
+        return [
+          ['-5'],
+          ['-5+10'],
+          ['4-5'],
+          ['4 -5'],
+          ['(4*2)-5'],
+          ['(4*2) - 5'],
+          ['4*-5'],
+          ['4 * -5'],
+          ['+5'],
+          ['+(3+2)'],
+          ['+(+3+2)'],
+          ['+(-3+2)'],
+          ['-5'],
+          ['-(-5)'],
+          ['-(+5)'],
+          ['+(-5)'],
+          ['+(+5)'],
+          ['-(3+2)'],
+          ['-(-3+-2)'],
+
+          ['abs(1.5)'],
+          ['acos(0.15)'],
+          ['acosh(1.5)'],
+          ['asin(0.15)'],
+          ['atan(0.15)'],
+          ['atan2(1.5, 3.5)'],
+          ['atanh(0.15)'],
+          ['bindec("10101")'],
+          ['ceil(1.5)'],
+          ['cos(1.5)'],
+          ['cosh(1.5)'],
+          ['decbin("15")'],
+          ['dechex("15")'],
+          ['decoct("15")'],
+          ['deg2rad(1.5)'],
+          ['exp(1.5)'],
+          ['expm1(1.5)'],
+          ['floor(1.5)'],
+          ['fmod(1.5, 3.5)'],
+          ['hexdec("abcdef")'],
+          ['hypot(1.5, 3.5)'],
+          ['intdiv(10, 2)'],
+          ['log(1.5)'],
+          ['log10(1.5)'],
+          ['log1p(1.5)'],
+          ['max(1.5, 3.5)'],
+          ['min(1.5, 3.5)'],
+          ['octdec("15")'],
+          ['pi()'],
+          ['pow(1.5, 3.5)'],
+          ['rad2deg(1.5)'],
+          ['round(1.5)'],
+          ['sin(1.5)'],
+          ['sin(12)'],
+          ['+sin(12)'],
+          ['-sin(12)', '0.53'],
+          ['sinh(1.5)'],
+          ['sqrt(1.5)'],
+          ['tan(1.5)'],
+          ['tanh(1.5)'],
+
+          ['0.1 + 0.2'],
+          ['0.1 + 0.2 - 0.3'],
+          ['1 + 2'],
+
+          ['0.1 - 0.2'],
+          ['1 - 2'],
+
+          ['0.1 * 2'],
+          ['1 * 2'],
+
+          ['0.1 / 0.2'],
+          ['1 / 2'],
+
+          ['2 * 2 + 3 * 3'],
+          ['2 * 2 / 3 * 3', '3.99'],
+          ['2 / 2 / 3 / 3', '0.11'],
+          ['2 / 2 * 3 / 3'],
+          ['2 / 2 * 3 * 3'],
+
+          ['1 + 0.6 - 3 * 2 / 50'],
+
+          ['(5 + 3) * -1'],
+
+          ['-2- 2*2'],
+          ['2- 2*2'],
+          ['2-(2*2)'],
+          ['(2- 2)*2'],
+          ['2 + 2*2'],
+          ['2+ 2*2'],
+          ['2+2*2'],
+          ['(2+2)*2'],
+          ['(2 + 2)*-2'],
+          ['(2+-2)*2'],
+
+          ['1 + 2 * 3 / (min(1, 5) + 2 + 1)'],
+          ['1 + 2 * 3 / (min(1, 5) - 2 + 5)'],
+          ['1 + 2 * 3 / (min(1, 5) * 2 + 1)'],
+          ['1 + 2 * 3 / (min(1, 5) / 2 + 1)'],
+          ['1 + 2 * 3 / (min(1, 5) / 2 * 1)'],
+          ['1 + 2 * 3 / (min(1, 5) / 2 / 1)'],
+          ['1 + 2 * 3 / (3 + min(1, 5) + 2 + 1)', '1.85'],
+          ['1 + 2 * 3 / (3 - min(1, 5) - 2 + 1)'],
+          ['1 + 2 * 3 / (3 * min(1, 5) * 2 + 1)', '1.85'],
+          ['1 + 2 * 3 / (3 / min(1, 5) / 2 + 1)'],
+
+          ['(1 + 2) * 3 / (3 / min(1, 5) / 2 + 1)'],
+
+          ['sin(10) * cos(50) / min(10, 20/2)', '-0.05'],
+          ['sin(10) * cos(50) / min(10, (20/2))', '-0.05'],
+          ['sin(10) * cos(50) / min(10, (max(10,20)/2))', '-0.05'],
+
+          ['1 + "2" / 3', '1.66'],
+          ["1.5 + '2.5' / 4", '2.12'],
+          ['1.5 + "2.5" * ".5"'],
+
+          ['-1 + -2'],
+          ['-1+-2'],
+          ['-1- -2'],
+          ['-1/-2'],
+          ['-1*-2'],
+
+          ['(1+2+3+4-5)*7/100'],
+          ['(-1+2+3+4- 5)*7/100'],
+          ['(1+2+3+4- 5)*7/100'],
+          ['( 1 + 2 + 3 + 4 - 5 ) * 7 / 100'],
+
+          ['1 && 0'],
+          ['1 && 0 && 1'],
+          ['1 || 0'],
+          ['1 && 0 || 1'],
+
+          ['5 == 3'],
+          ['5 == 5'],
+          ['5 != 3'],
+          ['5 != 5'],
+          ['5 > 3'],
+          ['3 > 5'],
+          ['3 >= 5'],
+          ['3 >= 3'],
+          ['3 < 5'],
+          ['5 < 3'],
+          ['3 <= 5'],
+          ['5 <= 5'],
+          ['10 < 9 || 4 > (2+1)'],
+          ['10 < 9 || 4 > (-2+1)'],
+          ['10 < 9 || 4 > (2+1) && 5 == 5 || 4 != 6 || 3 >= 4 || 3 <= 7'],
+
+          ['1 + 5 == 3 + 1'],
+          ['1 + 5 == 5 + 1'],
+          ['1 + 5 != 3 + 1'],
+          ['1 + 5 != 5 + 1'],
+          ['1 + 5 > 3 + 1'],
+          ['1 + 3 > 5 + 1'],
+          ['1 + 3 >= 5 + 1'],
+          ['1 + 3 >= 3 + 1'],
+          ['1 + 3 < 5 + 1'],
+          ['1 + 5 < 3 + 1'],
+          ['1 + 3 <= 5 + 1'],
+          ['1 + 5 <= 5 + 1'],
+
+          ['(-4)'],
+          ['(-4 + 5)'],
+          ['(3 * 1)'],
+          ['(-3 * -1)'],
+          ['1 + (-3 * -1)'],
+          ['1 + ( -3 * 1)'],
+          ['1 + (3 *-1)'],
+          ['1 - 0'],
+          ['1-0'],
+
+          ['-(1.5)'],
+          ['-log(4)', '-1.38'],
+          ['0-acosh(1.5)', '-0.96'],
+          ['-acosh(1.5)', '-0.96'],
+          ['-(-4)'],
+          ['-(-4 + 5)'],
+          ['-(3 * 1)'],
+          ['-(-3 * -1)'],
+          ['-1 + (-3 * -1)'],
+          ['-1 + ( -3 * 1)'],
+          ['-1 + (3 *-1)'],
+          ['-1 - 0'],
+          ['-1-0'],
+          ['-(4*2)-5'],
+          ['-(4*-2)-5'],
+          ['-(-4*2) - 5'],
+          ['-4*-5'],
+          ['max(1,2,4.9,3)'],
+          ['min(1,2,4.9,3)'],
+          ['max([1,2,4.9,3])'],
+          ['min([1,2,4.9,3])'],
+
+          ['4 % 4'],
+          ['7 % 4'],
+          ['99 % 4'],
+          ['123 % 7'],
         ];
     }
 
