Comparing floats

To compare floats use such a function:

// Return true if the values could be
// considered as equal by a precision.
function compareFloat($x, $y, $precision = 0.00001) {
    return abs($x - $y) < $precision;
}

In mysql you can search by float values with the same technique:

SELECT * FROM my_table
WHERE ABS(my_value - $iLookForThis) < 0.00001;