On this one, I really don't have a clue what is wrong with PHP. Run the script shown below. Results should be "c" == "d" == "e", but "e" is some other value. I noticed that if you comment out the "$temp_x = ..." line (which shouldn't matter anyway) you get the correct answer for "e". I need this to convert a vector to unit length (which should be simple enough) and I thought that I was going crazy.

If you want to see how PHP is configured, look here:
http://144.92.10.251/~sage/test.php

<?php
$temp_x = .0663;
$temp_y = .01486;

print "a=" . $temp_x . ", b=" . $temp_y . ", c=" .
	(.0148 / sqrt( .0663 * .0663 + .01486 * .01486 ) ) . ", d=" .
	($temp_y / sqrt( ( $temp_x * $temp_x ) + ( $temp_y * $temp_y ) ));

$temp_x = $temp_x / sqrt(($temp_x * $temp_x ) + ( $temp_y * $temp_y ) );

$temp_y = $temp_y / sqrt(($temp_x * $temp_x ) + ( $temp_y * $temp_y ) );

echo ", e=" . $temp_y;
?>