(PHP 4, PHP 5, PHP 7)
bcpow — Raise an arbitrary precision number to another
$base
, string $exponent
[, int $scale
= 0
] ) : string
Raise base
to the power
exponent
.
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.
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
scale
parameter 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"
?>