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Round to the nearest integral value
#include <math.h> double rint ( double x ); float rintf ( float x );
libm
Use the -l m option to qcc to link against this library.
The rint() and rintf() functions return the integral value nearest x in the direction of the current rounding mode.
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().
An integer (represented as a double precision number) nearest x in the direction of the current rounding mode (IEEE754).
If x is: | rint() returns: |
---|---|
±Infinity | x |
NAN | NAN |
If an error occurs, these functions return 0, but this is also a valid mathematical result. If you want to check for errors, set errno to 0, call the function, and then check errno again. These functions don't change errno if no errors occurred. |
#include <stdio.h> #include <errno.h> #include <inttypes.h> #include <math.h> #include <fpstatus.h> int main(int argc, char** argv) { double a, b; a = 0.7 ; b = rint(a); printf("Round Native mode %f -> %f \n", a, b); return(0); }
Safety: | |
---|---|
Cancellation point | No |
Interrupt handler | No |
Signal handler | No |
Thread | Yes |