# bcpow

(PHP 4, PHP 5, PHP 7)

bcpow — Raise an arbitrary precision number to another

### Description

bcpow ( string `$base` , string `$exponent` [, int `$scale` = 0 ] ) : string

Raise `base` to the power `exponent`.

### Parameters

`base`

  The base, as a string.

`exponent`

  The exponent, as a string. If the exponent is non-integral, it is truncated. The valid range of the exponent is platform specific, but is at least `-2147483648` to `2147483647`.

`scale`

  This optional parameter is used to set the number of digits after the decimal place in the result. If omitted, it will default to the scale set globally with the bcscale() function, or fallback to `0` if this has not been set.

### Return Values

Returns the result as a string.

### Changelog

Version | Description
--- | ---
7.3.0 | bcpow() now returns numbers with the requested scale. Formerly, the returned numbers may have omitted trailing decimal zeroes.

### Examples

Example #1 bcpow() example

`<?php
echo bcpow('4.2', '3', 2); // 74.08
?>`

### Notes

> Note:

> Before PHP 7.3.0 bcpow() may return a result with fewer digits after the decimal point than the `scale` parameter would indicate. This only occurs when the result doesn't require all of the precision allowed by the `scale`. For example:

> Example #2 bcpow() scale example

> `<?php
> echo bcpow('5', '2', 2); // prints "25", not "25.00"
> ?>`

### See Also

- bcpowmod() - Raise an arbitrary precision number to another, reduced by a specified modulus
- bcsqrt() - Get the square root of an arbitrary precision number