Formula1

Simple Mathematical formulas evaluator for PHP

If you need to evaluate a formula with basic operators and variables, and

• No eval: You dont want to use EVAL for obvious security reasons,
• No dependencies: You don't want to rely on half the internet as dependencies, but prefer a single self-contained class,
• Old PHP OK: You don't necessarily have the latest PHP version, or Composer,
• No spaghetti: You want something readable that you could easily understand and customize,
• Arithmetic rules OK: You need something that knows about operators priority, unary operators, and parenthesis,
• Rounding OK: You want to specify a precision and rounding mode for the result,
• Recursive eval: You want to be able to include sub-formulas inside your variables,

...then you might like Formula1 ! ;-)

Simple usage no variables

$f1 = new Formula1('-45+(41*2)-(6/(3+1))');
echo($f1->compute()); // 35.5

// With rounding (third and fourth params are precision and mode, like for the round function) 
$f1 = new Formula1('2/3', [], 3);
echo($f1->compute()); // 0.667

Simple usage with variables

$f1 = new Formula1('-45+(fourty_one*2)-(6/(three+1))' , ['fourty_one'=>41, 'three'=>3]);
echo($f1->compute()); // 35.5

Funky usage with variables that include formulas themselves (and recusrively)

$f1 = new Formula1('-45+(fourty_one*2)-(6/(three+1))' , ['fourty_one'=>'82/2', 'three'=>'12/four', 'four'=>4]);
echo($f1->compute()); // 35.5

TODO

• add math operations like sin, cos, sqrt etc...