Implement these operators for text-based I/O. They need to be global, not inside your class. However, you might need to make them friends of your class in order to access the internals.
(First the simple version)
Code:
std::ostream & operator <<(std::ostream &os, const Float &fl); // Output
std::istream & operator >>(std::istream &is, Float &fl); // Input
(And now the full-blow complete version)
Code:
template < typename C, class Traits >
std::basic_ostream<C, Traits> & operator <<(std::basic_ostream<C, Traits> &os, const Float &fl); // Output
template < typename C, class Traits >
std::basic_istream<C, Traits> & operator >>(std::basic_istream<C, Traits> &is, Float &fl); // Input