(PHP 5)
bcpowmod — Raise an arbitrary precision number to another, reduced by a specified modulus
$left_operand
, string $right_operand
, string $modulus
[, int $scale
] )
Use the fast-exponentiation method to raise
left_operand
to the power
right_operand
with respect to the modulus
modulus
.
left_operand
The left operand, as a string.
right_operand
The right operand, as a string.
modulus
The modulus, as a string.
scale
Acest parametru opțional este utilizat pentru a stabili numărul cifrelor după virgulă din rezultat. De asemenea puteți să stabiliți parametrul global scale pentru toate funcțiile utilizând bcscale().
Returns the result as a string, or NULL
if modulus
is 0.
Notă:
Because this method uses the modulus operation, numbers which are not positive integers may give unexpected results.
The following two statements are functionally identical. The bcpowmod() version however, executes in less time and can accept larger parameters.
<?php
$a = bcpowmod($x, $y, $mod);
$b = bcmod(bcpow($x, $y), $mod);
// $a and $b are equal to each other.
?>