INFINITY
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                    | Defined in header  <cmath> | ||
| #define INFINITY /*implementation defined*/ | (since C++11) | |
If the implementation supports floating-point infinities, the macro INFINITY expands to constant expression of type float which evaluates to positive or unsigned infinity.
If the implementation does not support floating-point infinities, the macro INFINITY expands to a positive value that is guaranteed to overflow a float at compile time, and the use of this macro generates a compiler warning.
See also
| (C++11) | checks if the given number is infinite (function) | 
| (C++11)(C++11) | indicates the overflow value for float, double and long double respectively (macro constant) | 
| [static] | identifies floating-point types that can represent the special value "positive infinity" (public static member constant of std::numeric_limits<T>) | 
| [static] | returns the positive infinity value of the given floating-point type (public static member function of std::numeric_limits<T>) |