NAME
floor() — floor function
SYNOPSIS
#include <math.h>
double floor(double x);
DESCRIPTION
floor()
returns the largest integer (represented as a double-precision number)
not greater than
x.
To use this function, make sure your program includes
<math.h>,
and link in the math library by specifying
-lm
on the compiler or linker command line.
RETURN VALUE
If
x
is ±INFINITY or ±zero,
floor()
returns
x.
If
x
is NaN,
floor()
returns NaN.
If the correct value would overflow,
floor()
returns
-HUGE_VAL
and sets
errno
to [ERANGE]. (This description complies with XPG4.2; however, the
floor()
function never overflows on HP-UX systems.)
ERRORS
If
floor()
fails,
errno
is set to the following value.
- [ERANGE]
The correct value would overflow.
STANDARDS CONFORMANCE
floor(): SVID3, XPG4.2, ANSI C