git: 9front

ref: b0ab2a2ded1ecfcf5ad17d2016870a5431b6e805
dir: /sys/src/ape/lib/ap/math/floor.c/

View raw version 
#include <math.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);
}