logb man page on SmartOS

Man page or keyword search:  
man Server   16655 pages
apropos Keyword Search (all sections)
Output format
SmartOS logo
[printable version]

logb(3M)		Mathematical Library Functions		      logb(3M)

NAME
       logb, logbf, logbl - radix-independent exponent

SYNOPSIS
       c99 [ flag... ] file... -lm [ library... ]
       #include <math.h>

       double logb(double x);

       float logbf(float x);

       long double logbl(long double x);

       cc [ flag... ] file... -lm [ library... ]
       #include <math.h>

       double logb(double x);

       float logbf(float x);

       long double logbl(long double x);

DESCRIPTION
       These  functions	 compute the exponent of x, which is the integral part
       of log(r) |x|, as a signed floating point value, for non-zero x,	 where
       r is the radix of the machine's floating-point arithmetic, which is the
       value of FLT_RADIX defined in the <float.h> header.

RETURN VALUES
       Upon successful completion, these functions return the exponent of x.

       If x is subnormal:

	   o	  For SUSv3-conforming applications compiled with the c99 com‐
		  piler	 driver	 (see standards(5)), the exponent of x as if x
		  were normalized is returned.

	   o	  Otherwise, if compiled with the cc compiler  driver,	−1022,
		  −126,	 and  −16382  are  returned  for  logb(), logbf(), and
		  logbl(), respectively.

       If x is ±0, a pole error occurs and logb(), logbf(), and logbl() return
       −HUGE_VAL, −HUGE_VALF, and −HUGE_VALL, respectively.

       If x is NaN, a NaN is returned.

       If x is ±Inf, +Inf is returned.

ERRORS
       These functions will fail if:

       Pole Error    The value of x is ±0.

		     If the integer expression (math_errhandling & MATH_ERREX‐
		     CEPT)  is	non-zero,  the	divide-by-zero	floating-point
		     exception is raised.

		     The  logb() function sets errno to EDOM if the value of x
		     is 0.

USAGE
       An application wanting to check for exceptions should  call  feclearex‐
       cept(FE_ALL_EXCEPT)  before  calling  these  functions.	On  return, if
       fetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is
       non-zero,  an  exception	 has been raised. An application should either
       examine the return value or check the floating point exception flags to
       detect exceptions.

       An  application	can  also  set	errno  to  0 before calling logb(). On
       return, if errno is non-zero, an error has occurred.  The  logbf()  and
       logbl() functions do not set errno.

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       ┌─────────────────────────────┬─────────────────────────────┐
       │      ATTRIBUTE TYPE	     │	    ATTRIBUTE VALUE	   │
       ├─────────────────────────────┼─────────────────────────────┤
       │Interface Stability	     │Standard			   │
       ├─────────────────────────────┼─────────────────────────────┤
       │MT-Level		     │MT-Safe			   │
       └─────────────────────────────┴─────────────────────────────┘

SEE ALSO
       feclearexcept(3M),  fetestexcept(3M),  ilogb(3M),  math.h(3HEAD), math‐
       err(3M), scalb(3M), attributes(5), standards(5)

SunOS 5.11			  12 Jul 2006			      logb(3M)
[top]

List of man pages available for SmartOS

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net