Order of operations between powers and multiplications

[daniel-cabane]

Describe the bug
The order of operations between powers and multiplications is not what I expect

To Reproduce
Steps to reproduce the behavior:

$evaluator = new \Matex\Evaluator();
$evaluator->execute(4*3^2); // returns 144
$evaluator->execute(45/3^2); // returns 225

Expected behavior
Following usual PEDMAS order of operations, powers should be computed before multiplications and/or divisions.
The above code should then return 36 on line 2 and 5 on line 3

[mccarlosen]

In these cases, you must use the mathematical association operator. It would look like this:

$evaluator = new \Matex\Evaluator();
$evaluator->execute('4*(3^2)'); // returns 36
$evaluator->execute('45/(3^2)'); // returns 5

[daniel-cabane]

This would indeed return the correct result but it does not really solve my problem. My app uses randomly generated math expressions (which are later displayed in Latex format) so adding parenthesis where necessary would be quite a painful process.
Besides, PEDMAS is the most commonly accepted convention for the order of operation (as far as I know). I think it would be to this library's benefit to follow it.

[ghost]

I think this is a pretty fundamental flaw in an expression evaluator, and agree implementing it in the package itself rather than working around it would be preferable. I'm taking a look at the source trying to understand where the order of operations is defined, but I'm having a hard time.

[mccarlosen]

If you need something much more complete to work with complex and dynamic expressions, I advise you to use this symfony component: Expression Language

https://gist.github.com/mccarlosen/ddf4b923da2a49442ae2344b850e282c

[ghost]

If you need something much more complete to work with complex and dynamic expressions, I advise you to use this symfony component: Expression Language

https://gist.github.com/mccarlosen/ddf4b923da2a49442ae2344b850e282c

Thank you, that is for sure a very viable alternative, but doesn't change the fact that this is a mathematical expression evaluator, and as such it should be able to evaluate according to the standard order of operations.