BC Math 函数
在线手册：中文 英文
PHP手册

bcmod

(PHP 4, PHP 5)

bcmod — Get modulus of an arbitrary precision number

说明

string bcmod ( string $left_operand , string $modulus )

Get the modulus of the left_operand using modulus.

参数

left_operand

The left operand, as a string.

modulus

The modulus, as a string.

返回值

Returns the modulus as a string, or NULL if modulus is 0.

范例

Example #1 bcmod() example

<?php
echo bcmod('4', '2'); // 0
echo bcmod('2', '4'); // 2
?>

参见

BC Math 函数
在线手册：中文 英文
PHP手册
PHP手册 - N: Get modulus of an arbitrary precision number

用户评论:

ArleCamille (okw1003 at gmail dot com) (16-Nov-2009 12:47)

GCD made in Euclidian algorithm:
<?php
function bcgcd($a, $b)
{
    if($a < $b)
    {
        $t = $b;
        $b = $a;
        $a = $t;
        unset($t);
    }
    if(bcmod($a, $b) == "0") return $b;
    else return bcgcd($b, bcmod($a, $b));
}
?>
hope this helps.

mcuelenaere at gmail dot com (21-Dec-2007 09:00)

Heres an useful IBAN generate function:

<?php
function controleer_iban($iban) {
    $iban = str_replace(array(" ", "  ", "   ", "\t"), "", $iban);
    $iban = strtoupper(str_replace(" ", "", $iban));
    if(strlen($iban)>34)
        return false;
    $acceptabel = "A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 1 2 3 4 5 6 7 8 9 0";
    $acceptabel = explode(" ", $acceptabel);
    for($i = 0; $i<strlen($iban); $i++) {
        if(in_array(substr($iban, $i, 1), $acceptabel) === false)
            return false;
    }
    $alfa = "A B C D E F G H I J K L M N O P Q R S T U V W X Y Z";
    $alfa = explode(" ", $alfa);
    for($i = 1; $i<27; $i++) {
        $alfa_replace[] = $i+9;
    }
    $controlegetal = str_replace($alfa, $alfa_replace, substr($iban, 4, strlen($iban)-4).substr($iban, 0, 2)."00");
    $controlegetal = 98 - (int)bcmod($controlegetal,97);
    if((int)$controlegetal === (int)substr($iban, 2, 2))
        return true;
    else
        return false;   
}
?>

sebas at stageprikbord dot nl (27-Mar-2007 02:53)

function bc_is_even($int_str) {
  return (int)!($int_str & 1);
}

More resource efficient version of 'bc_is_even'.

lauris at night dot lt (23-Dec-2003 04:04)

<?php
/**
 * my_bcmod - get modulus (substitute for bcmod)
 * string my_bcmod ( string left_operand, int modulus )
 * left_operand can be really big, but be carefull with modulus :(
 * by Andrius Baranauskas and Laurynas Butkus :) Vilnius, Lithuania
 **/
function my_bcmod( $x, $y )
{
    // how many numbers to take at once? carefull not to exceed (int)
    $take = 5;    
    $mod = '';

    do
    {
        $a = (int)$mod.substr( $x, 0, $take );
        $x = substr( $x, $take );
        $mod = $a % $y;   
    }
    while ( strlen($x) );

    return (int)$mod;
}

// example
echo my_bcmod( "7044060001970316212900", 150 );
?>