downloads | documentation | faq | getting help | mailing lists | licenses | wiki | reporting bugs | php.net sites | conferences | my php.net

search for in the

gmp_div_q> <gmp_cmp
[edit] Last updated: Fri, 17 May 2013

view this page in

gmp_com

(PHP 4 >= 4.0.4, PHP 5)

gmp_comCalculates one's complement

Descrierea

resource gmp_com ( resource $a )

Returns the one's complement of a.

Parametri

a

Aceasta poate fi sau o resursă număr GMP, sau un șir de caractere numeric, dacă este posibilă convertirea acestuia într-un număr.

Valorile întoarse

Returns the one's complement of a, as a GMP number.

Exemple

Example #1 gmp_com() example

<?php
$com 
gmp_com("1234");
echo 
gmp_strval($com) . "\n";
?>

Exemplul de mai sus va afișa:

-1235


add a note add a note User Contributed Notes gmp_com - [1 notes]
up
0
xo at jdbartlett dot com
3 years ago
If you're using one's compliment (bitwise NOT) to flip all $a's bits, don't forget that you need to use a mask to specify how many bits you expect in your result:

<?php gmp_and(gmp_com('1234'), '2047') ?>
>> 813 // 01100101101 in binary

I chose 2047 because 1234 is an 11-bit binary number and 2047 is the maximum an 11-bit register can hold:

11111111111  (2047)
10011010010  (1234)
01100101101  (813)

 
show source | credits | stats | sitemap | contact | advertising | mirror sites