It's a floating point number: there are limits to its precision. You've only got 2^64 bits to work with. See http://en.wikipedia.org/wiki/Floating_point http:/

It's a floating point number: there are limits to its precision. You've only got 2^64 bits to work with. See http://en.wikipedia.org/wiki/Floating_point http://en.wikipedia.org/wiki/Floating_point