diff options
Diffstat (limited to 'src/ste/Calc.php')
| -rw-r--r-- | src/ste/Calc.php | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/src/ste/Calc.php b/src/ste/Calc.php index e8dba8d..595a7d6 100644 --- a/src/ste/Calc.php +++ b/src/ste/Calc.php @@ -5,7 +5,7 @@ namespace kch42\ste; /* Class Calc contains static methods needed by <ste:calc /> */ class Calc { private function __construct() {} - + /* We could also just eval() the $infix_math code, but this is much cooler :-D (Parser inception) */ public static function shunting_yard($infix_math) { $operators = array( @@ -18,12 +18,12 @@ class Calc { "(" => array("", 0), ")" => array("", 0) ); - + preg_match_all("/\s*(?:(?:[+\\-\\*\\/\\^\\(\\)])|(\\d*[\\.]?\\d*))\\s*/s", $infix_math, $tokens, PREG_PATTERN_ORDER); $tokens_raw = array_filter(array_map('trim', $tokens[0]), function($x) { return ($x === "0") || (!empty($x)); }); $output_queue = array(); $op_stack = array(); - + $lastpriority = NULL; /* Make - unary, if neccessary */ $tokens = array(); @@ -37,7 +37,7 @@ class Calc { } $lastpriority = $priority; } - + while(!empty($tokens)) { $token = array_shift($tokens); if(is_numeric($token)) { @@ -73,7 +73,7 @@ class Calc { $op_stack[] = $token; } } - + while(!empty($op_stack)) { $op = array_pop($op_stack); if($op == "(") { @@ -81,10 +81,10 @@ class Calc { } $output_queue[] = $op; } - + return $output_queue; } - + public static function pop2(&$array) { $rv = array(array_pop($array), array_pop($array)); if(array_search(NULL, $rv, true) !== false) { @@ -92,7 +92,7 @@ class Calc { } return $rv; } - + public static function calc_rpn($rpn) { $stack = array(); foreach($rpn as $token) { @@ -131,7 +131,7 @@ class Calc { } return array_pop($stack); } - + public static function calc($expr) { return self::calc_rpn(self::shunting_yard($expr)); } |