ilogb(3M)ilogb(3M)NAMEilogb(), ilogbf(), ilogbl(), ilogbw(), ilogbq() - radix-independent
exponent functions
SYNOPSIS
Integrity Server Only
DESCRIPTION
The function computes the exponent of the floating point value x. For‐
mally, the return value is the integral part of log base r of |x| as a
signed integral value, for nonzero x, where r is the radix of the
machine's floating-point arithmetic. The radix r is 2 on HP-UX sys‐
tems.
If x is denormal it is treated as though it were normalized before the
exponent is determined.
Note: is equivalent to for all values of x
Integrity Servers Only
is a version of it takes a argument.
is a version of it takes a argument.
is an version of it takes an argument.
is equivalent to on HP-UX systems.
USAGE
To use these functions, compile either with the default option or with
the and options.
To use (for Integrity servers) or compile also with the option.
Make sure your program includes Link in the math library by specifying
on the compiler or linker command line.
For more information, see the at the following site:
RETURN VALUE
If x is NaN, returns
If x returns
If x is zero, returns
Integrity Servers Only
If x is NaN, +-INFINITY, or zero, then the invalid floating-point
exception is raised (as specified by C99 TC2)
The macros and are defined in
ERRORS
No errors are defined.
SEE ALSOfrexp(3M), logb(3M), scalb(3M), scalbn(3M), scalbln(3M), math(5).
STANDARDS CONFORMANCE
: XPG4.2, ISO/IEC C99 (including Annex F, "IEC 60559 floating-point
arithmetic")
: ISO/IEC C99 (including Annex F, "IEC 60559 floating-point arith‐
metic")
ilogb(3M)