(PHP 4 >= 4.0.4, PHP 5)
gmp_hamdist — Hamming distance
Returns the hamming distance between a and b . Both operands should be non-negative.
It can be either a GMP number resource, or a numeric string given that it is possible to convert the latter to a number.
It should be positive.
It can be either a GMP number resource, or a numeric string given that it is possible to convert the latter to a number.
It should be positive.
A GMP number resource.
Example #1 gmp_hamdist() example
<?php
$ham1 = gmp_init("1001010011", 2);
$ham2 = gmp_init("1011111100", 2);
echo gmp_hamdist($ham1, $ham2) . "\n";
/* hamdist is equivilent to: */
echo gmp_popcount(gmp_xor($ham1, $ham2)) . "\n";
?>
上例将输出：
6 6