GMP Functions
PHP Manual

gmp_hamdist

Hamming distance

Description

int gmp_hamdist ( GMP $a , GMP $b )

Returns the hamming distance between a and b. Both operands should be non-negative.

Parameters

a

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.

It should be positive.

b

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.

It should be positive.

Return Values

A GMP number resource in PHP 5.5 and earlier, or a GMP object in PHP 5.6 and later.

Examples

Example #1 gmp_hamdist example

<?php
$ham1 = gmp_init("1001010011", 2);
$ham2 = gmp_init("1011111100", 2);
echo gmp_hamdist($ham1, $ham2) . "\n";

/* hamdist is equivalent to: */
echo gmp_popcount(gmp_xor($ham1, $ham2)) . "\n";
?>

The above example will output:

6
6

See Also

  • gmp_popcount
  • gmp_xor