gmp_hamdist

(PHP 4 >= 4.0.4, PHP 5)

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

The above example will output:

6
6

See Also

Коментарии

Автор:
For those without gmp support :

$hamming_distance = count(array_diff_assoc(str_split($string1), str_split($string2)));

And if you are not sure if your strings have equal length :

$hamming_distance = count(array_diff_assoc(str_split(str_pad($string1,strlen($string2)-strlen($string1),' ')), str_split(str_pad($string2,strlen($string1)-strlen($string2),' '))));
2018-04-16 08:41:00
http://php5.kiev.ua/manual/ru/function.gmp-hamdist.html
<?php
$hamdist 
gmp_hamdist(-100, -10); // 4
$hamdist gmp_hamdist(10010);  // 5
?>

The function works great with negative numbers.
2021-03-11 13:14:43
http://php5.kiev.ua/manual/ru/function.gmp-hamdist.html

    Поддержать сайт на родительском проекте КГБ