(PHP 8 >= 8.4.0)
BcMath\Number::pow — Raises an arbitrary precision number
Raises $this to the exponent power.
exponentexponent is platform specific,
but it is at least -2147483648 to 2147483647.
scalenull, the BcMath\Number::scale of the calculation result will be set automatically.
Returns the result of power as a new BcMath\Number object.
When the BcMath\Number::scale of the result object is automatically set,
depending on the value of exponent, the BcMath\Number::scale
of result will be as follows:
exponent |
BcMath\Number::scale of result |
|---|---|
| positive | (BcMath\Number::scale of power base) * (exponent's value) |
0 |
0 |
| negative | Between (BcMath\Number::scale of power base) and (BcMath\Number::scale
of power base + 10) |
If an indivisible division occurs due to a negative exponent, the
BcMath\Number::scale of the result is expanded. Expansion is done only as needed, up to
a maximum of +10.
This behavior is the same as BcMath\Number::div(), so please see that for details.
This method throws a ValueError in the following cases:
exponent is string and not a well-formed BCMath numeric stringexponent has a fractional partexponent or scale is outside the valid range
This method throws a DivisionByZeroError exception if $this's value
is 0 and exponent is a negative value.
Example #1 BcMath\Number::pow() example when scale is not specified
<?php
$number = new BcMath\Number('3.0');
$ret1 = $number->pow(new BcMath\Number('5'));
$ret2 = $number->pow('-1');
$ret3 = $number->pow(0);
var_dump($number, $ret1, $ret2, $ret3);
?>The above example will output:
object(BcMath\Number)#1 (2) {
["value"]=>
string(3) "3.0"
["scale"]=>
int(1)
}
object(BcMath\Number)#3 (2) {
["value"]=>
string(9) "243.00000"
["scale"]=>
int(5)
}
object(BcMath\Number)#2 (2) {
["value"]=>
string(13) "0.33333333333"
["scale"]=>
int(11)
}
object(BcMath\Number)#4 (2) {
["value"]=>
string(1) "1"
["scale"]=>
int(0)
}
Example #2 BcMath\Number::pow() example of explicitly specifying scale
<?php
$number = new BcMath\Number('3.0');
$ret1 = $number->pow(new BcMath\Number('5'), 0);
$ret2 = $number->pow('-1', 2);
$ret3 = $number->pow(0, 10);
var_dump($number, $ret1, $ret2, $ret3);
?>The above example will output:
object(BcMath\Number)#1 (2) {
["value"]=>
string(3) "3.0"
["scale"]=>
int(1)
}
object(BcMath\Number)#3 (2) {
["value"]=>
string(3) "243"
["scale"]=>
int(0)
}
object(BcMath\Number)#2 (2) {
["value"]=>
string(4) "0.33"
["scale"]=>
int(2)
}
object(BcMath\Number)#4 (2) {
["value"]=>
string(12) "1.0000000000"
["scale"]=>
int(10)
}