INFINITY
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                    |   Defined in header  <cmath>
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|   #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>)  | 
|   C documentation for INFINITY 
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