PHP | gmp_neg() Function

The gmp_neg() function is an in-built function in PHP which returns the negative of a GMP number (GNU Multiple Precision).

Syntax :

gmp_neg( $num  )

Parameters : The function accepts only one mandatory parameter $num which can be either a GMP number resource in PHP 5.5 or a GMP object in PHP version 5.6 and later, or numeric strings can be passed to the function provided that it is possible to convert those strings to numbers.

Return Values : This function returns a GMP number (in PHP 5.5 and earlier) or a GMP object (in PHP 5.6 and later) which is negative of the value of $num.

Examples :

Input : $num = 255 
Output : -255

Input : $num = 128 
Output : -128

Below programs will illustrate the gmp_neg() function :

Program 1:

<?php
//PHP program to illustrate
//gmp_neg() function

$num = gmp_init("255");

$num1 = gmp_neg($num);

echo gmp_strval($num1);
?>

Output:

-255

Program 2:

<?php
//PHP program to illustrate
//gmp_neg() function

$num = gmp_init("314567128");

$num1 = gmp_neg($num);

echo gmp_strval($num1);
?>

Output:

-314567128

Reference : http://php.net/manual/en/function.gmp-neg.php