Well, to begin with applying the mask 1111 0000 to 1101 0100 0110 0110 is going to give you 1100000 not 110. But you can shift the result to the right 4 if that is the result you want. There is no algorithm to speak of here, just apply the mask. Like this:
$num = "1101010001100110"; $mask = "11110000"; $result = bindec($num) & bindec($mask); echo decbin($result); If you want only the second quartet of the result, do: $result = $result>>4; -Rasmus On Wed, 28 Aug 2002, David Buerer wrote: > Here's a question, > > Say I have a binary number like this > > 1101 0100 0110 0110 > > And I want to pull out of the binary number the third quartet (is that the > right word) > > I want to know how to apply the mask > > 0000 1111 0000 0000 > > to the number above so that the result would be > 0100 > > Likewise, given > the number: 1101 0100 0110 0110 > and the mask 0000 0000 1111 0000 > the result 0110 > > I suppose this is the same algorithm used to separate the host from the node > address given an IP address and a subnet mask. I just need to know what the > algorithm is. > > Thanks > David > > -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php