NAME
ilogb —
return exponent as an integer
value
SYNOPSIS
#include
<math.h>
int
ilogb(double
x);
int
ilogbl(long
double x);
int
ilogbf(float
x);
DESCRIPTION
The
ilogb()
functions return the exponent of x as a signed integer value.
SPECIAL VALUES
ilogb(±0)
returns FP_ILOGB0.
ilogb(±infinity)
returns INT_MAX.
ilogb(x)
returns FP_ILOGBNAN if x is a NaN.
A range error may occur if x is 0, ±infinity, or a nan.
The special return values FP_ILOGB0 and FP_ILOGBNAN are defined in math.h, and may differ between platforms. INT_MAX is defined in limits.h.
SEE ALSO
STANDARDS
The ilogb() functions conform to ISO/IEC
9899:2011.