PHP | gmp_pow() Function

The gmp_pow() is an inbuilt function in PHP which is used to calculate the power raised to a number of a GMP number and an integer (GNU Multiple Precision: For large numbers).

Syntax:

gmp_pow( $base, $exp )

Parameters: The function accepts two mandatory parameters $base and $exp.

1. $base – It is the base number. This parameter can be a GMP object in PHP version 5.6 and later, or we are also allowed to pass a numeric string provided that it is possible to convert that string to a number.
2. $exp – It is the power which is raised to the base

Return Value: This function returns a positive GMP number which is equivalent to $base^$exp
Examples:

Input : $base = "2" $exp = 2
Output : 4

Input : $base = "0" $exp = 0
Output : 1 

Below programs illustrate the gmp_pow() function:

Program 1: The program below demonstrates the working of gmp_pow() function when GMP number is passed as an argument.

<?php
// PHP program to calculate power raised
// to a number

// GMP number as argument
$base = gmp_init("100", 2);
$exp = 2;

// function calculates the pow raised to
// number
$pow = gmp_pow($base, $exp);  // 4^2

// gmp_strval Convert GMP number to string
// representation in given base(default 10).
echo gmp_strval($pow, 2) . "\n";
?>

Output:

10000

Program 2: The program below demonstrates the working of gmp_pow() when numeric string is passed as an argument.

<?php
// PHP program to calculate power raised
// to a number

// numeric string as argument
$base = "4";
$exp = 2;

// function calculates the pow raised to
// number  4^2
$pow = gmp_pow($base, $exp);

echo $pow;
?>

Output:

10000

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