Updated: April 19, 2023 |
Round to the nearest integral value
#include <math.h> double rint ( double x ); float rintf ( float x ); long double rintl( long double x );
Your system requirements will determine how you should work with these libraries:
The rint(), rintf(), and rintl() functions return the integral value nearest x in the direction of the current rounding mode (see fesetround()).
If the current rounding mode rounds toward negative infinity, then rint() is identical to floor(). If the current rounding mode rounds toward positive infinity, then rint() is identical to ceil().
To check for error situations, use feclearexcept() and fetestexcept(). For example:
An integer (represented as a double precision number) nearest x in the direction of the current rounding mode. The result has the same sign as x.
If x is: | rint() returns: | Errors: |
---|---|---|
±Inf | x | — |
NaN | x | — |
These functions raise FE_INEXACT if the FPU reports that the result can't be exactly represented as a floating-point number.
#include <stdio.h> #include <math.h> #include <fenv.h> #include <stdlib.h> int main( void ) { int except_flags; double a, b; feclearexcept(FE_ALL_EXCEPT); a = 0.7 ; b = rint(a); except_flags = fetestexcept(FE_ALL_EXCEPT); if(except_flags) { /* An error occurred; handle it appropriately. */ } printf("Round Native mode %f -> %f \n", a, b); return EXIT_SUCCESS; }
Safety: | |
---|---|
Cancellation point | No |
Interrupt handler | Yes |
Signal handler | Yes |
Thread | Yes |