NAME

floor, floorf, ceil, ceilf, copysign, fmod, fmodf, fabs, fabsf, rint, remainder − floor, ceiling, remainder, absolute value functions

SYNOPSIS

cc [flag ...] file ... −lm [library ...]

#include <math.h>

double floor (double x);

float floorf (float x);

double ceil (double x);

float ceilf (float x);

double copysign (double x, double y);

double fmod (double x, double y);

float fmodf (float x, float y);

double fabs (double x);

float fabsf (float x);

double rint (double x);

double remainder (double x, double y);

DESCRIPTION

floor and floorf return the largest integer not greater than x. ceil and ceilf return the smallest integer not less than x.

copysign returns x but with the sign of y.

fmod and fmodf return the floating point remainder of the division of x by y. More precisely, they return the number f with the same sign as x, such that x = iy + f for some integer i, and | f| <| y|.

fabs and fabsf return the absolute value of x, | x|.

rint returns the nearest integer value to its floating point argument x as a double-precision floating point number.  The returned value is rounded according to the currently set machine rounding mode.  If round-to-nearest (the default mode) is set and the difference between the function argument and the rounded result is exactly 0.5, then the result will be rounded to the nearest even integer. 

remainder returns the floating point remainder of the division of x by y. More precisely, it returns the value r = x − yn, where n is the integer nearest the exact value x/y.  Whenever | n − x/y| = ½, then n is even. 

SEE ALSO

abs(3C), matherr(3M)

DIAGNOSTICS

fmod and fmodf return x when y is 0 and set errno to EDOM.  remainder returns NaN when y is 0 and sets errno to EDOM.  In both cases, except in compilation modes −Xa or −Xc, a message indicating DOMAIN error is printed on the standard error output.  Except under −Xc, these error-handling procedures may be changed with the function matherr. 

  —  Math Libraries