C/C++ NaN constant (literal)?

Question

Is this possible to assign a NaN to a double or float in C/C++? Like in JavaScript you do: a = NaN. So later you can chec

Answer 1

In C, NAN is declared in .

In C++, std::numeric_limits::quiet_NaN() is declared in .

But for checking whether a value is NaN, you can't compare it with another NaN value. Instead use isnan() from in C, or std::isnan() from in C++.