path for "include" statement

[wheel]

I've had my developer write an ajax script for use on someone else's blog. In the php script he's used an include statement for a couple of calculator type functions.

include "calculator.php";

let's say we drop that script into their /blog directory. Someone visits the post, the script works fine, it can find calculator.php.
But what happens once that page gets archived? Now it's going to be accessed like /blog/archives/2010/blogpost. Will the include statement still work? I'm thinking not.

[rocknbil]

This will always find it, wherever it lives.

include($_SERVER['DOCUMENT_ROOT'] . '/path_to/calculator.php');

Best case for using full paths, same for URL's:

src="/images/somefile.jpg"

not

src="images/somefile.jpg"

[wheel]

Excellent! Thank you rocknbill :). I appreciate the assistance.