Determines whether x is less than y. Format #include <math.h> int isless (x, y);
1 – Arguments
x,y Values to be compared.
2 – Description
The function fails if one of the arguments is NaN. This causes an exception. To avoid this, C99 defines the macro isless (x, y), which determines (x) < (y) without an exception if x or y is NaN. The macro is guaranteed to evaluate the arguments only once. The arguments must be of real floating-point type. Note: Do not pass integer values as arguments to this macro because the arguments will not be promoted to real floating-point types.
3 – Return Values
The isless (x, y) macro returns the result of the relational comparison. It returns 0 if either argument is a NaN.