Studying for my PHP Cert.

[Michael Dick]

I ran across a question about using basic operators...but it seemed to use a "<<" operator and it is no where to be found on Google nor any books I have laying around?

Anyhelp!?

Thanks

[.josh]

[a href=\"http://us2.php.net/manual/en/language.operators.bitwise.php\" target=\"_blank\"]http://us2.php.net/manual/en/language.operators.bitwise.php[/a]

[Michael Dick]

Life saver, thanks.

[Michael Dick]

Hmm, I can't really get a grasp on it...

Help would be appreciated...THANKS!

[.josh]

bitwise operators are used in doing binary math. Just like doing normal base 10 math that you are used to, except for in base 2.

let's say you have this:

$a = 16;
echo $a << 2;

$a would echo 64. why? well lets look at those numbers in base 2:

00010000 // this is 16 in base 10
01000000 // this is 64 in base 10

$a << 2 shifts the bit over 2 'spaces'. all 8 of those 'spaces' is called a byte. each space is called a bit. now you might better understand this in terms of kilobytes, megabytes, gigabytes, etc.. well this is the base level of that.

here is a really good tutoral on binary mathematics:

[a href=\"http://www.litfuel.net/tutorials/bitwise.htm\" target=\"_blank\"]http://www.litfuel.net/tutorials/bitwise.htm[/a]