Formula1

##Simple Mathematical formulas evaluator for PHP

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

You dont want to use EVAL for obvious security reasons,
You don't want to rely on half the internet as dependancies, but prefer a single self-contained class,
You don't necessarily have the latest PHP version, or Composer,
You want something readable that you could easily understand and customize,
You need something that knows about operators priority, unary operators, and parenthesis,
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

Simple usage with variables

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

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());

##TODO