GMP Functions

Ver también

More mathematical functions can be found in the Mathematical Extensions section

gmp_abs — Valor absoluto
gmp_add — Suma números
gmp_and — Realiza una operación de AND lógico
gmp_clrbit — Borra un bit
gmp_cmp — Compara números
gmp_com — Calcula el complementario
gmp_div_q — Divide números
gmp_div_qr — Divide números y obtiene el cociente y el resto
gmp_div_r — Resto de la división de números
gmp_div — Alias of gmp_div_q
gmp_divexact — División exacta de números
gmp_fact — Factorial
gmp_gcd — Calcula el MCD (máximo común divisor)
gmp_gcdext — Calcula el MCD y los coeficientes
gmp_hamdist — Distancia de Hamming
gmp_init — Crea un número GMP
gmp_intval — Convierte números GMP a números enteros
gmp_invert — Invierte según el módulo
gmp_jacobi — Calcula el símbolo de Jacobi
gmp_legendre — Calcula el símbolo de Legendre
gmp_mod — Operación Módulo
gmp_mul — Multiplica números
gmp_neg — Cambia el signo de un número
gmp_nextprime — Find next prime number
gmp_or — Realiza una operación de OR lógico
gmp_perfect_square — Comprueba si es un cuadrado perfecto
gmp_popcount — Calcula la población de un número
gmp_pow — Eleva un número a una potencia
gmp_powm — Eleva un número a una potencia según el módulo
gmp_prob_prime — Comprueba si un número tiene probabilidades de ser un número primo
gmp_random — Genera un número aleatorio
gmp_scan0 — Busca un 0
gmp_scan1 — Busca un 1
gmp_setbit — Establece el valor de un bit
gmp_sign — Obtiene el signo del número
gmp_sqrt — Calcula la raíz cuadrada
gmp_sqrtrem — Calcula la raíz cuadrada con el resto
gmp_strval — Convierte un número GMP a una cadena de texto
gmp_sub — Resta números
gmp_testbit — Tests if a bit is set
gmp_xor — Realiza una operación de XOR lógico

gmp_abs

GMP

Last updated: Fri, 22 Aug 2008

add a note User Contributed Notes
GMP Functions

john at worldmapad dot com
23-Jul-2006 09:24


Here's a quick and dirty way to use simple GMP functions with PHP without recompiling. It is dependent upon the use of the exec() function, so make sure you can use exec(). While in safe mode you must consider the safe_mode_exec_dir directive. And don't simply pass user input to the exec function without validating the input first!



Download and Install GMP as instructed in README and INSTALL files.

On my MAC OS X Server, I just did the following:

./configure

make

make check

make install

This installed it in the /usr/local directory. There were some errors, but not with any functions I needed.

Within the gmp-4.#.# cd into the demos directory. Then compile pexpr.c by typing:

make pexpr

This is a simple expressions parser which serves as a simple interface to some of the basic GMP functions.

You can test it then like:

./pexpr "102394874783 * 23498748";

Now you may interface with it using PHP's exec() function.

richard-slater.co.uk
22-Feb-2004 11:03


For those (like me) who are trying to do bit masking with very large numbers, here is a useful function to do the work for you.



<?php

  function isBitSet($bitMask, $bitMap)

  {

    return (bool) gmp_intval(gmp_div(gmp_and($bitMask, $bitMap),$bitMask));

  }

?>

helvecio_oliveira at yahoo dot com dot br
15-Oct-2003 11:51


=============================================================

A set of very nice functions to handle IP Address with gmplib:



The best way to store a range into a database is store:

dNet ..... decimal representation of a Net

dMask .... decimal representation of a Mask



All another parameters can be calculated.



<?

/*

f_ip2dec($a) ................... IP string to decimal

f_dec2ip($a) ................... decimal to IP string



f_dec2ipall($dNet,$dMask) ...... decimal Net and Mask to an Array with several IP parameters



f_dec2cidr($a) ................. decimal Mask to CIDR



f_and($a,$b) ................... and

f_or($a,$b) .................... or

f_xor($a,$b) ................... xor

f_not($a) ...................... not

f_dec2bin($a) .................. decimal to binary string

f_bin2dec($a) .................. binary string to decimal

*/



function f_and($a,$b){

$a=gmp_init(strval($a));

$b=gmp_init(strval($b));

$d=gmp_and($a,$b);

return floatval(gmp_strval($d));

}



function f_or($a,$b){

$a=gmp_init(strval($a));

$b=gmp_init(strval($b));

$d=gmp_or($a,$b);

return floatval(gmp_strval($d));

}



function f_xor($a,$b){

$a=gmp_init(strval($a));

$b=gmp_init(strval($b));

$d=gmp_xor($a,$b);

return floatval(gmp_strval($d));

}



function f_not($a){

$a=gmp_init(strval($a));

$d=gmp_strval($a,2);

$d=str_replace("1","x",$d);

$d=str_replace("0","1",$d);

$d=str_replace("x","0",$d);

$d=gmp_init($d,2);

return floatval(gmp_strval($d,10));

}



function f_dec2bin($a){

$a=gmp_init(strval($a));

return gmp_strval($a,2);

}



function f_bin2dec($a){

$a=gmp_init(strval($a),2);

return floatval(gmp_strval($a,10));

}



function f_ip2dec($a){

$d = 0.0;

$b = explode(".", $a,4);

for ($i = 0; $i < 4; $i++) {

        $d *= 256.0;

        $d += $b[$i];

    };

return $d;

}



function f_dec2ip($a){

    $b=array(0,0,0,0);

    $c = 16777216.0;

    $a += 0.0;

    for ($i = 0; $i < 4; $i++) {

        $k = (int) ($a / $c);

        $a -= $c * $k;

        $b[$i]= $k;

        $c /=256.0;

    };

    $d=join('.', $b);

    return($d);

}



function f_dec2cidr($a){

$a=gmp_init(strval($a));

$d=strlen(str_replace("0","",gmp_strval($a,2)));

return $d;

}



function f_dec2ipall($dNet,$dMask){

  $dWildCard=f_not($dMask);

  $IpAll["Net"]=f_dec2ip($dNet);

  $IpAll["Mask"]=f_dec2ip($dMask);

  $IpAll["WildCard"]=f_dec2ip($dWildCard);

  $IpAll["Cidr"]=f_dec2cidr($dMask);

  $IpAll["Bcast"]=f_dec2ip(f_or($dNet,$dWildCard));

  $IpAll["nIp"]=$dWildCard+1;

  $IpAll["nIpUtil"]=$dWildCard-1;

  if($IpAll["nIp"] > 2){

        $IpAll["IpFrom"]=f_dec2ip($dNet+1);

        $IpAll["IpTo"]=f_dec2ip($dNet+$dWildCard-1);

  }

  else

  {

        $IpAll["IpFrom"]="-";

        $IpAll["IpTo"]="-";

        $IpAll["nIpUtil"]=0;

  }

  return $IpAll;

}



?>



=============================================================

GMP install steps in Mandrake 9.1: 

----------------------------------------------------------

cp -r /usr/src/php-devel/extensions/gmp /tmp/gmp

cd /tmp/gmp

phpize

./configure

make install

echo "extension = gmp.so" > /etc/php/90_gmp.ini



Restart apache web server.

----------------------------------------------------------

gmp.so is in:

/usr/lib/php/extensions/



look in phpinfo, the string:

/etc/php/90_gmp.ini 



Needs these tools:

autoconf

automake

libtool

m4

php430-devel-430-11mdk.rpm

all rpm�s that are envolved to run and compile gmp (*gmp*.rpm)



Some docs about self contained extensions:

/usr/share/doc/php430-devel-430/SELF-CONTAINED-EXTENSIONS

=============================================================

add a note

gmp_abs

GMP

Last updated: Fri, 22 Aug 2008

GMP Functions

Ver también

Table of Contents