(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)
gmp_prob_prime — Check if number is "probably prime"
The function uses Miller-Rabin's probabilistic test to check if a number is a prime.
num
The number being checked as a prime.
Ein GMP-Object, ein Integer oder eine numeriche Zeichenkette.
repetitions
Reasonable values of repetitions
vary from 5 to 10 (default being 10); a higher value lowers the probability for a non-prime to pass as a "probable" prime.
Ein GMP-Object, ein Integer oder eine numeriche Zeichenkette.
If this function returns 0, num
is definitely not prime. If it returns 1, then num
is "probably" prime. If it returns 2, then num
is surely prime.
Beispiel #1 gmp_prob_prime() example
<?php
// definitely not a prime
echo gmp_prob_prime("6") . "\n";
// probably a prime
echo gmp_prob_prime("1111111111111111111") . "\n";
// definitely a prime
echo gmp_prob_prime("11") . "\n";
?>
Das oben gezeigte Beispiel erzeugt folgende Ausgabe:
0 1 2