[Boost-users] [lexical_cast] float-to-string rounding error (not found with cout)

I'm seeing unexpected behavior when using lexical_cast<string>. This code: const float f = 00123.12300; cout << f << endl; cout << boost::lexical_caststd::string(f) << endl; gives the result: 123.123 123.123001 Two questions: (1) Is there a way to eliminate this trailing '1' with lexical_cast (presumably some wierd rounding error)? (2) When casting float-to-string, given this behavior, why should I use lexical_cast instead of, say, stringstream? Thanks -Grant