PHP Manual: Exponential expression

Description

number pow ( number $base , number $exp )

Returns base raised to the power of exp.

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 integer type, otherwise it will be returned as a float.

Changelog

Version	Description
4.2.0	No warning is emitted on errors, even if the value can't be computed.
4.0.6	The function will now return integer results if possible, before this it always returned a float result. For older versions, you may receive a bogus result for complex numbers.

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(-1, 5.5); // PHP >4.0.6  NAN
echo pow(-1, 5.5); // PHP <=4.0.6 1.#IND
?>

Notes

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

pow