Hi tobaccofarm, In addition to what Wolfgang mentioned, the %f specifies a float, not a double. The %lf specifies a double (which you are using), and %Lf specifies a long double. Since in C (as I recall, prehaps incorrectly), a float is promoted to a double before passing into the printf routine, I'm not sure if that means that %f and %lf have the same behavior. Just a FYI, in case it is relevant. HTH, --Eljay