(PHP 4, PHP 5)
pow — Exponential expression
Returns base raised to the power of
exp.
Note:
In PHP 5.6 onwards, you may prefer to use the ** operator.
baseThe base to use
expThe exponent
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.
| 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. |
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
?>
Note:
This function will convert all input to a number, even non-scalar values, which could lead to weird results.