Funções da GMP
PHP Manual

gmp_random_range

(PHP 5 >= 5.6.3, PHP 7)

gmp_random_rangeRandom number

Descrição

GMP gmp_random_range ( GMP $min , GMP $max )

Generate a random number. The number will be between min and max.

min and max can both be negative but min must always be less than max.

Parâmetros

min

A GMP number representing the lower bound for the random number

max

A GMP number representing the upper bound for the random number

Valor Retornado

A random GMP number.

Exemplos

Exemplo #1 gmp_random_range() example

<?php
$rand1 
gmp_random_range(0100);    // random number between 0 and 100
$rand2 gmp_random_range(-100, -10); // random number between -100 and -10

echo gmp_strval($rand1) . "\n";
echo 
gmp_strval($rand2) . "\n";
?>

O exemplo acima irá imprimir:

42
-67


Funções da GMP
PHP Manual