Dear Prof Hwang!

is it possible to eliminate rounding off error in this simulation calculation?

http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=2067.msg8920#msg8920

notice the
L1 = 10.416 = 10.42
L2 = 9.393 = 9.38
delta L = 10.33 = 10.3

but 10.42-9.38 =! 10.3 but actually = 10.4