How do I calculate a math expression in the form of a string to an output using PHP?
<?php
$ma ="min(2+10,5*1,max(8/2,8-2,abs(-10)))"; // math expression
print $ma; // output of the calculation
?>
2 Answers
I made a math_eval helper function package that should do exactly want you need.
Example usage:
require 'vendor/autoload.php';
$two = math_eval('1 + 1');
$three = math_eval('5 - 2');
$ten = math_eval('2 * 5');
$four = math_eval('8 / 2');
Link: https://github.com/langleyfoxall/math_eval
In the background, this wraps around the mossadal/math-parser package.
2 Comments
I've found some parsers on GitHub, this one looks very interesting:
mossadal/math-parser: PHP parser for mathematical expressions
It can be used this way:
use MathParser\StdMathParser;
use MathParser\Interpreting\Evaluator;
$parser = new StdMathParser();
// Generate an abstract syntax tree
$AST = $parser->parse('1+2');
// Do something with the AST, e.g. evaluate the expression:
$evaluator = new Evaluator();
$value = $AST->accept($evaluator);
echo $value;
It can also be used with functions like cos() or sin().
eval, but mind you, this comes with serious security issues.evalis probably the right answer, however this does feel like an XY problem question