ref: 0feb6e06af1e48c2b1a937c6a593fceeafd728d2
dir: /sys/src/libc/port/floor.c/
#include <u.h>
#include <libc.h>
/*
* floor and ceil-- greatest integer <= arg
* (resp least >=)
*/
double
floor(double d)
{
double fract;
if(d < 0) {
fract = modf(-d, &d);
if(fract != 0.0)
d += 1;
d = -d;
} else
modf(d, &d);
return d;
}
double
ceil(double d)
{
return -floor(-d);
}