Q:

function to get the subtraction result state that is it positive or negative?

I am performing subtraction on two variable. 
$first_variable = 20;
$second_variable = 30;
$result = $first_variable - $second_variable;

So how do i get that the result $result is positive or negative? 
Have any PHP function to determine that the result of subtraction is positive or negative? 
I know the i can use if statement to get it done. but i am asking for any predefined function to do it.
The reason i asked it hear is just a curiosity. 

A:

You can use php gmp_sign function to achieve that check this
Example:-
<?php
// positive
echo gmp_sign("500") . "\n";

// negative
echo gmp_sign("-500") . "\n";

// zero
echo gmp_sign("0") . "\n";
?>

output
1
-1
0

