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pow

(PHP 4, PHP 5, PHP 7)

pow — Exponential expression

Description

pow ( int|float $base , int|float $exp ) : int|float

Returns base raised to the power of exp.

Note:

In PHP 5.6 onwards, you may prefer to use the ** operator.

Parameters

base

The base to use

exp

The exponent

Return Values

base raised to the power of exp. If both arguments are non-negative integers and the result can be represented as an integer, the result will be returned with int type, otherwise it will be returned as a float.

Examples

Example #1 Some examples of pow()

<?php

var_dump(pow(2, 8)); // int(256)
echo pow(-1, 20); // 1
echo pow(0, 0); // 1
echo pow(10, -1); // 0.1

echo pow(-1, 5.5); // PHP >=5.2.2: NAN
echo pow(-1, 5.5); // PHP <5.2.2: -NAN
?>

Notes

Note:

This function will convert all input to a number, even non-scalar values, which could lead to weird results.

See Also

  • exp() - Calculates the exponent of e
  • sqrt() - Square root
  • bcpow() - Raise an arbitrary precision number to another
  • gmp_pow() - Raise number into power

© 1997–2020 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.pow.php