Check if number is "probably prime"

Açıklama

int gmp_prob_prime ( GMP $a [, int $reps = 10 ] )

The function uses Miller-Rabin's probabilistic test to check if a number is a prime.

Değiştirgeler

a

The number being checked as a prime.

Either a GMP number resource in PHP 5.5 and earlier, a GMP object in PHP 5.6 and later, or a numeric string provided that it is possible to convert the latter to a number.

reps

Reasonable values of reps vary from 5 to 10 (default being 10); a higher value lowers the probability for a non-prime to pass as a "probable" prime.

Either a GMP number resource in PHP 5.5 and earlier, a GMP object in PHP 5.6 and later, or a numeric string provided that it is possible to convert the latter to a number.

Dönen Değerler

If this function returns 0, a is definitely not prime. If it returns 1, then a is "probably" prime. If it returns 2, then a is surely prime.

Örnekler

Örnek 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";
?>

Yukarıdaki örneğin çıktısı:

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