# gmp_hamdist

(PHP 4 >= 4.0.4, PHP 5)

gmp_hamdist — Hamming distance

### Description

int gmp_hamdist ( resource `$a` , resource `$b` )

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

### Parameters

`a`

  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.

`b`

  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.

### Return Values

A GMP number resource.

### Examples

Example#1 gmp_hamdist() example

`<?php
$ham1 = gmp_init("1001010011", 2);
$ham2 = gmp_init("1011111100", 2);
echo gmp_hamdist($ham1, $ham2) . "\n";
/* hamdist is equivilent to: */
echo gmp_popcount(gmp_xor($ham1, $ham2)) . "\n";
?>`

The above example will output:

    6
    6

### See Also

- gmp_popcount()
- gmp_xor()