isless
From cppreference.com
                    
                                        
                    
                    
                                                            
                    | Defined in header  <math.h> | ||
| #define isless(x, y) /* implementation defined */ | (since C99) | |
Determines if the floating point number x is less than the floating-point number y, without setting floating-point exceptions.
| Contents | 
[edit] Parameters
| x | - | floating point value | 
| y | - | floating point value | 
[edit] Return value
Nonzero integral value if x < y, 0 otherwise
[edit] Notes
The built-in operator< for floating-point numbers may raise FE_INVALID if one or both of the arguments is NaN. This function is a "quiet" version of operator<.
[edit] Example
Run this code
Possible output:
isless(2.0,1.0) = 0 isless(1.0,2.0) = 1 isless(INFINITY,1.0) = 0 isless(1.0,NAN) = 0
[edit] See also
| (C99) | checks if the first floating-point argument is greater than the second (function) | 
| C++ documentation for isless | |


