function base_convert($numstring, $frombase, $tobase)
{
if (function_exists('gmp_strval')) {
return gmp_strval(gmp_init($numstring, $frombase), $tobase);
} else {
if (function_exists('bi_base_convert')) {
return bi_base_convert($numstring, $frombase, $tobase);
} else {
return oidUtilPhpBigInt::_base_convert($numstring, $frombase, $tobase);
}
}
}
/*
second argument of bi_from_str() and bi_to_str() - is the base
of string representation of number. It can be from 2 to 36 inclusive
*/
$str = 'abcdef012789';
echo 'hex value of $str = [', $str, "]<br/>\n";
$b = bi_from_str($str, 16);
echo 'decimal value of $b = [', bi_to_str($b), "]<br/>\n";
echo 'binary value of $b = [', bi_to_str($b, 2), "]<br/>\n";
/*
string bi_base_convert(string $num, int $base_from, int $base_to)
Converts string representation of $num from base $base_from to $base_to
*/
$num = '-12345678900987654321';
echo 'Decimal number [', $num, '] equals to [', bi_base_convert($num, 10, 36), '] by base 36', "<br/>\n";
/*
basic functions
*/
echo '<h3>basic functions</h3>' . "\n";
$c = bi_add($a, $b);
echo '$a + $b = [', bi_to_str($c), "]<br/>\n";
$c = bi_sub($a, $b);
echo '$a - $b = [', bi_to_str($c), "]<br/>\n";
$c = bi_mul($a, $b);
echo '$a * $b = [', bi_to_str($c), "]<br/>\n";
$c = bi_div($a, $b);
echo '$a / $b = [', bi_to_str($c), "]<br/>\n";
$c = bi_mod($a, $b);
echo '$a % $b = [', bi_to_str($c), "]<br/>\n";
$c = bi_abs($a);
