(PHP 4, PHP 5, PHP 7, PHP 8)
bcpow — Raise an arbitrary precision number to another
$num, string $exponent, ?int $scale = null): string
Raise num to the power
exponent.
numThe 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.
scaleThis 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.
Returns the result as a string.
| Version | Description |
|---|---|
| 7.3.0 | bcpow() now returns numbers with the requested scale. Formerly, the returned numbers may have omitted trailing decimal zeroes. |
Example #1 bcpow() example
<?php
echo bcpow('4.2', '3', 2); // 74.08
?>
Note:
Before PHP 7.3.0 bcpow() may return a result with fewer digits after the decimal point than the
scaleparameter would indicate. This only occurs when the result doesn't require all of the precision allowed by thescale. For example:Example #2 bcpow() scale example
<?php
echo bcpow('5', '2', 2); // prints "25", not "25.00"
?>