PHP: pow - Manual (original) (raw)

(PHP 4, PHP 5, PHP 7, PHP 8)

pow — Exponential expression

Description

Note:

It is possible to use the ** operator instead.

Parameters

num

The base to use

exponent

The exponent

Return Values

num raised to the power of exponent. 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.

PHP-Extensions may override the behaviour of this operation and make it return an object.

Changelog

Examples

Example #1 Some examples of pow()

`<?php

var_dump

(pow(2, 8)); // int(256)
echo pow(-1, 20), PHP_EOL; // 1
echo pow(0, 0), PHP_EOL; // 1
echo pow(10, -1), PHP_EOL; // 0.1echo pow(-1, 5.5), PHP_EOL; // NAN
?>`

Example #2 Examples of pow() With GMP Extension Object

<?php var_dump(pow(new GMP("3"), new GMP("2"))); // object(GMP) ?>

Notes

Note:

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

See Also

• Exponentiation operator**
• fpow() - Raise one number to the power of another, according to IEEE 754
• exp() - Calculates the exponent of e
• sqrt() - Square root
• bcpow() - Raise an arbitrary precision number to another
• gmp_pow() - Raise number into power

Found A Problem?

gilthansREMOVEME at gmail dot com ¶

19 years ago

Note that pow(0, 0) equals to 1 although mathematically this is undefined.

Roman ¶

5 years ago

If you use negative numbers, you need to use brackets for using with **

<?php

-1 ** 2; // -1

(-1) ** 2; // 1

?>